U.S. patent number 10,154,420 [Application Number 15/288,852] was granted by the patent office on 2018-12-11 for user equipment, network node and methods therein.
This patent grant is currently assigned to Telefonaktiebolaget L M Ericsson (publ). The grantee listed for this patent is TELEFONAKTIEBOLAGET LM ERICSSON (PUBL). Invention is credited to Ali Behravan, Muhammad Kazmi.
United States Patent |
10,154,420 |
Behravan , et al. |
December 11, 2018 |
User equipment, network node and methods therein
Abstract
Embodiments herein relate to a method in a user equipment (10)
for performing a radio measurement in a communications network (1),
which user equipment (10) is In Device Coexistent, IDC, capable and
being served by a network node (12,13) in the communications
network (1). The user equipment (10) receives, from the network
node (12,13), an IDC configuration for at least one IDC scheme; and
the user equipment (10) performs a radio measurement which meets
one or more requirements related to the radio measurement provided
the received IDC configuration meets a certain condition.
Inventors: |
Behravan; Ali (Stockholm,
SE), Kazmi; Muhammad (Bromma, SE) |
Applicant: |
Name |
City |
State |
Country |
Type |
TELEFONAKTIEBOLAGET LM ERICSSON (PUBL) |
Stockholm |
N/A |
SE |
|
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Assignee: |
Telefonaktiebolaget L M Ericsson
(publ) (Stockholm, SE)
|
Family
ID: |
50385086 |
Appl.
No.: |
15/288,852 |
Filed: |
October 7, 2016 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20170026865 A1 |
Jan 26, 2017 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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13860325 |
Nov 15, 2016 |
9497644 |
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61708340 |
Oct 1, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
H04B
15/00 (20130101); H04W 24/02 (20130101); H04W
24/00 (20130101); H04W 24/10 (20130101); H04W
72/1215 (20130101); H04W 88/02 (20130101) |
Current International
Class: |
H04W
24/10 (20090101); H04W 24/00 (20090101); H04B
15/00 (20060101); H04W 24/02 (20090101); H04W
88/02 (20090101); H04W 72/12 (20090101) |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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102687548 |
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Oct 2015 |
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CN |
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WO 2012/041255 |
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Apr 2012 |
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WO |
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WO 2012/047001 |
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Apr 2012 |
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WO |
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WO 2012/051952 |
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Apr 2012 |
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WO |
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WO 2012/124918 |
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Sep 2012 |
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WO |
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WO 2012/130175 |
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Oct 2012 |
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WO |
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WO 2013/085256 |
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Jun 2013 |
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WO |
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WO 2013/100658 |
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Jul 2013 |
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WO |
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WO 2013/170210 |
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Nov 2013 |
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WO |
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Other References
"3rd Generation Partnership Project; Technical Specification Group
Radio Access Network; Evolved Universal Terrestrial Radio Access
(E-UTRA); Study on signalling and procedure for interference
avoidance for in-device coexistence (Release 11)", 3GPP TR 36.816
v11.0.0, Jun. 2011, the whole document. cited by applicant .
CMCC. Kick-off of WI on Signalling and Procedure for Interference
Avoidance for In-Device Coexistence. 3GPP Draft; R2-115010 Kick-Off
of WI on Signalling and Procedure for Interference Avoidance for
In-Device Coexistence, 3.sup.rd Generation Partnership Project
(3GPP), Mobile Competence Centre; 650, Route Des Lucioles; F-06921
Sophia-Antipolis Cedex; FR. vol. RAN WG2, No. Zhuhai; Oct. 10,
2011, Oct. 4, 2011 (Oct. 4, 2011), the whole document. cited by
applicant .
Ericsson/ST-Ericsson, Analysis of RRM requirements, 3GPP TSG-RAN
WG4#64bis, R4-125803, Oct. 12, 2012, the whole document. cited by
applicant .
New Postcom, The remaining issues of IDC procedure, 3GPP TSG-RAN
WG2#79bis, R2-124745, Sep. 28, 2012, the whole document. cited by
applicant .
Qualcomm Incorporate, "Report of Email discussion [78#51] LTE/IOC:
Autonomous Denials," 3GPP TSG RAN WG2 Meeting #79, R2-123813, Aug.
6, 2012, the whole document. cited by applicant .
Samsung, "RRM/CQI/RLM measurement in different phases of IDC," 3GPP
TSG-RAN WG2 Meeting #79bis, R2-124772, Sep. 28, 2012, the whole
document. cited by applicant .
3rd Generation Partnership Project; Technical Specification Group
Radio Access Networks; Evolved Universal Terrestrial Radio Access
(E-UTRA); Study on Signalling and Procedure for Interference
Avoidance for In-Device Coexistence; (Release 10). 3GPP Standard;
3GPP TR 36.816, 3.sup.rd Generation Partnership Project (3GPP),
Mobile Competence Centre; 650, Route Deslucioles; F-06921
Sophia-Antipolis Cedex; France, No. v1.0.0, Dec. 17, 2010 (Dec. 17,
2010), the whole document. cited by applicant .
3GPP TR 36.816 V11.2.0, "3.sup.rd Generation Partnership Project;
Technical Specification Group Radio Access Network; Evolved
Universal Terrestrial Radio Access (E-UTRA); Study on signalling
and procedure for interference avoidance for in-device
coexistence", Release 11, Jan. 3, 2012, the whole document. cited
by applicant .
3GPP TS 36.321 V11.0.0 "3d Generation Partnership Project;
Technical Specification Group Radio Access Network; Evolved
Universal Terrestrial Radio Access (E-UTRA); Evolved Universal
Terrestrial Radio Access (E-UTRA); Medium Access Control (MAC)
protocol specification", Release 11, Sep. 24, 2012, the whole
document. cited by applicant.
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Primary Examiner: Qin; Zhiren
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of U.S. patent application Ser.
No. 13/860,325, filed on Apr. 10, 2013, now U.S. Pat. No.
9,497,644, which claims the benefit of U.S. Provisional Patent
Application 61/708,340 filed Oct. 1, 2012 and is also cross
referenced with the granted U.S. patent application Ser. No.
13/860,378 entitled "USER EQUIPMENT, NETWORK NODE AND METHODS
THEREIN" (now U.S. Pat. No. 9,185,573), which is commonly owned.
The cross referenced U.S. patent application Ser. No. 13/860,378
and the parent U.S. patent application Ser. No. 13/860,325 are
incorporated herein by reference.
Claims
What is claimed is:
1. A method in a user equipment which is In Device Coexistent, IDC,
capable and being served by a network node in a communications
network, the method comprising: receiving, by the user equipment
from the network node, an IDC configuration; and performing a radio
measurement which meets one or more requirements related to the
radio measurement provided the received IDC configuration meets a
certain condition where the received IDC configuration comprises
not more than a preset number of IDC autonomous denial subframes
over a certain IDC autonomous denial validity period; and, wherein
the certain condition ensures that the user equipment adapts an
autonomous denial such that the adapted autonomous denial does not
coincide with the measurement sampling instances but rather where
the adapted autonomous denial falls within successive measurement
samples whereby the successive measurement samples are saved and an
accuracy of the radio measurement is not impacted so as to meet the
one or more requirements.
2. The method of claim 1, further comprising: determining that the
received IDC configuration comprises not more than the preset
number of IDC autonomous denial subframes over the certain IDC
autonomous denial validity period.
3. The method of claim 1, further comprising: reporting a
capability of the user equipment to the network node, wherein the
capability indicates that the user equipment is capable of
performing the radio measurement which meets the one or more
requirements related to the radio measurement provided the IDC
configuration comprises not more than the preset number of IDC
autonomous denial subframes over the certain IDC autonomous denial
validity period.
4. The method of claim 1, wherein the radio measurement when
performed is ensured to result in a reliable radio measurement that
meets the one or more requirements because the received IDC
configuration comprises not more than the preset number of IDC
autonomous denial subframes over the certain IDC autonomous denial
validity period.
5. The method of claim 1, wherein the radio measurement is based on
multiple samples which are received over a measurement period in
which the radio measurement is performed.
6. The method of claim 5, wherein a number of the multiple samples
is reduced when the user equipment autonomously denies some
sub-frames.
7. The method of claim 1, wherein the preset number of IDC
autonomous denial subframes is 30 subframes and the certain IDC
autonomous denial validity period is at least 200 milliseconds.
8. The method of claim 1, wherein: the radio measurement is a
handover radio measurement, a positioning radio measurement, or a
mobility radio measurement; and, the one or more requirements are
pre-defined performance requirements.
9. A user equipment which is In Device Coexistent (IDC) capable and
is configured to be served by a network node in a communications
network, the user equipment comprising: a processor; and, a memory
that stores computer program code, wherein the processor interfaces
with the memory to execute the computer program code, whereby the
user equipment is configured to: receive, from the network node, an
IDC configuration; and perform a radio measurement which meets one
or more requirements related to the radio measurement provided the
received IDC configuration meets a certain condition where the
received IDC configuration comprises not more than a preset number
of IDC autonomous denial subframes over a certain IDC autonomous
denial validity period; and wherein the certain condition ensures
that the user equipment adapts an autonomous denial such that the
adapted autonomous denial does not coincide with the measurement
sampling instances but rather where the adapted autonomous denial
falls within successive measurement samples whereby the successive
measurement samples are saved and an accuracy of the radio
measurement is not impacted so as to meet the one or more
requirements.
10. The user equipment of claim 9, wherein the user equipment is
further configured to: determine that the received IDC
configuration comprises not more than the preset number of IDC
autonomous denial subframes over the certain IDC autonomous denial
validity period.
11. The user equipment according to claim 9, wherein the user
equipment is further configured to: report a capability of the user
equipment to the network node, wherein the capability indicates
that the user equipment is capable of performing the radio
measurement which meets the one or more requirements related to the
radio measurement provided the IDC configuration comprises not more
than the preset number of IDC autonomous denial subframes over the
certain IDC autonomous denial validity period.
12. The user equipment of claim 9, wherein the radio measurement
when performed is ensured to result in a reliable radio measurement
that meets the one or more requirements because the received IDC
configuration comprises not more than the preset number of IDC
autonomous denial subframes over the certain IDC autonomous denial
validity period.
13. The user equipment of claim 9, wherein the radio measurement is
based on multiple samples which are received over a measurement
period in which the radio measurement is performed.
14. The user equipment of claim 13, wherein a number of the
multiple samples is reduced when the user equipment autonomously
denies some sub-frames.
15. The user equipment of claim 9, wherein the preset number of IDC
autonomous denial subframes is 30 subframes and the certain IDC
autonomous denial validity period is at least 200 milliseconds.
16. The user equipment of claim 9, wherein: the radio measurement
is a handover radio measurement, a positioning radio measurement,
or a mobility radio measurement; and, the one or more requirements
are pre-defined performance requirements.
17. A method in a network node enables a user equipment to perform
a radio measurement in a communications network, wherein the user
equipment is In Device Coexistent (IDC) capable and being served by
the network node in the communications network, the method
comprising: configuring, by a processor in the network node, the
user equipment with an IDC configuration comprising IDC autonomous
denial parameters, which the IDC configuration configures the user
equipment to perform the radio measurement which meets one or more
requirements related to the radio measurement provided the IDC
configuration meets a certain condition where the IDC configuration
comprises not more than a preset number of IDC autonomous denial
subframes over a certain IDC autonomous denial validity period;
and, wherein the certain condition ensures that the user equipment
adapts an autonomous denial such that the adapted autonomous denial
does not coincide with the measurement sampling instances but
rather where the adapted autonomous denial falls within successive
measurement samples whereby the successive measurement samples are
saved and an accuracy of the radio measurement is not impacted so
as to meet the one or more requirements.
18. The method of claim 17, further comprising: determining, by the
processor in the network node, the IDC configuration according to a
rule that will at least one of (1) ensure consistent user equipment
behaviour, and (2) ensure that the user equipment meets one or more
requirements related to the radio measurement.
19. The method of claim 17, prior to the configuring step further
comprising: receiving, by the network node, a report from the user
equipment indicating a capability of the user equipment, wherein
the capability indicates that the user equipment is capable of
performing the radio measurement.
20. The method of claim 19, further comprising at least one of:
determining, after the receiving step and prior to the configuring
step, the IDC configuration based on the received capability; and
performing, after the configuring step, one or more radio operation
tasks or actions based on the received capability.
21. The method of claim 17, wherein the configuring the user
equipment with the IDC configuration ensures that the user
equipment performs a reliable radio measurement that meets the one
or more requirements because the IDC configuration comprises not
more than a preset number of IDC autonomous denial subframes over a
certain IDC autonomous denial validity period.
22. The method of claim 17, wherein the radio measurement is based
on multiple samples which are received over a measurement period in
which the radio measurement is performed.
23. The method of claim 22, wherein a number of the multiple
samples is reduced when the user equipment autonomously denies some
sub-frames.
24. The method of claim 17, wherein the preset number of IDC
autonomous denial subframes is 30 subframes and the certain IDC
autonomous denial validity period is at least 200 milliseconds.
25. The method of claim 17, wherein: the radio measurement is a
handover radio measurement, a positioning radio measurement, or a
mobility radio measurement; and, the one or more requirements are
pre-defined performance requirements.
26. A network node configured to enable a user equipment to perform
a radio measurement in a communications network, wherein the user
equipment is In Device Coexistent (IDC) capable and the network
node is configured to serve the user equipment in the
communications network, the network node comprising: a processor;
and, a memory that stores computer program code, wherein the
processor interfaces with the memory to execute the computer
program code, whereby the network node is configured to: configure
the user equipment with an IDC configuration comprising IDC
autonomous denial parameters, which the IDC configuration
configures the user equipment to perform the radio measurement
which meets one or more requirements related to the radio
measurement provided the IDC configuration meets a certain
condition where the IDC configuration comprises not more than a
preset number of IDC autonomous denial subframes over a certain IDC
autonomous denial validity period; and, wherein the certain
condition ensures that the user equipment adapts an autonomous
denial such that the adapted autonomous denial does not coincide
with the measurement sampling instances but rather where the
adapted autonomous denial falls within successive measurement
samples whereby the successive measurement samples are saved and an
accuracy of the radio measurement is not impacted so as to meet the
one or more requirements.
27. The network node of claim 26, wherein the network node is
further configured to: determine the IDC configuration according to
a rule that will at least one of (1) ensure consistent user
equipment behaviour, and (2) ensure that the user equipment meets
one or more requirements related to the radio measurement.
28. The network node of claim 26, wherein the network node prior to
the configure operation is further configured to: receive a report
from the user equipment indicating a capability of the user
equipment, wherein the capability indicates that the user equipment
is capable of performing the radio measurement which meets the one
or more requirements related to the radio measurement provided an
IDC configuration comprises not more than the preset number of IDC
autonomous denial subframes over the certain IDC autonomous denial
validity period.
29. The network node of claim 28, wherein the network node is
further configured to perform at least one of following: determine,
after the receive operation and prior to the configure operation,
the IDC configuration based on the received capability; and
perform, after the configure operation, one or more radio operation
tasks or actions based on the received capability.
30. The network node of claim 26, wherein the configuring the user
equipment with the IDC configuration ensures that the user
equipment performs a reliable radio measurement that meets the one
or more requirements because the IDC configuration comprises not
more than a preset number of IDC autonomous denial subframes over a
certain IDC autonomous denial validity period.
31. The network node of claim 26, wherein the radio measurement is
based on multiple samples which are received over a measurement
period in which the radio measurement is performed.
32. The network node of claim 31, wherein a number of the multiple
samples is reduced when the user equipment autonomously denies some
sub-frames.
33. The network node of claim 26, wherein the preset number of IDC
autonomous denial subframes is 30 subframes and the certain IDC
autonomous denial validity period is at least 200 milliseconds.
34. The network node of claim 26, wherein: the radio measurement is
a handover radio measurement, a positioning radio measurement, or a
mobility radio measurement; and, the one or more requirements are
pre-defined performance requirements.
Description
TECHNICAL FIELD
The present disclosure generally relates to a user equipment, a
network node, and methods therein, and more particularly relates to
user equipments that are capable of in device coexistence.
BACKGROUND
In a typical radio communications network, wireless terminals, also
known as mobile stations and/or user equipments (UEs), communicate
via a Radio Access Network (RAN) to one or more core networks. The
RAN covers a geographical area which is divided into cell areas,
with each cell area being served by a base station, e.g., a radio
base station (RBS), which in some networks may also be called, for
example, a "NodeB" in Universal Mobile Telecommunications System
(UMTS) or "eNodeB" in Long Term Evolution (LTE). A cell is a
geographical area where radio coverage is provided by the radio
base station at a base station site or an antenna site in case the
antenna and the radio base station are not collocated. Each cell is
identified by an identity within the local radio area, which is
broadcast in the cell. Another identity identifying the cell
uniquely in the whole mobile network is also broadcasted in the
cell. One base base stations communicate over the air interface
operating on radio frequencies with the user equipments within
range of the base stations.
In some versions of the RAN, several base stations may be
connected, e.g., by landlines or microwave, to a controller node,
such as a radio network controller (RNC) or a base station
controller (BSC), which supervises and coordinates various
activities of the plural base stations connected thereto. The RNCs
are typically connected to one or more core networks.
A UMTS is a third generation mobile communication system, which
evolved from the second generation (2G) Global System for Mobile
Communications (GSM). The UMTS Terrestrial Radio Access Network
(UTRAN) is essentially a RAN using Wideband Code Division Multiple
Access (WCDMA) and/or High Speed Packet Access (HSPA) for user
equipments. In a forum known as the Third Generation Partnership
Project (3GPP), telecommunications suppliers propose and agree upon
standards for e.g. third generation networks and further
generations, and investigate enhanced data rate and radio
capacity.
Specifications for the Evolved Packet System (EPS) have been
completed within the 3GPP and this work continues in the coming
3GPP releases. The EPS comprises the Evolved Universal Terrestrial
Radio Access Network (E-UTRAN), also known as the LTE radio access,
and the Evolved Packet Core (EPC), also known as System
Architecture Evolution (SAE) core network. E-UTRAN/LTE is a variant
of a 3GPP radio access technology wherein the radio base stations
are directly connected to the EPC core network rather than to RNCs.
In general, in E-UTRAN/LTE the functions of a RNC are distributed
between the radio base stations, e.g., eNodeBs in LTE, and the core
network. As such, the RAN of an EPS has an essentially "flat"
architecture comprising radio base stations without reporting to
RNCs.
In today's mobile user equipments (UE), multiple radio transceivers
are packaged inside the same device. A UE can be equipped with
external wireless system i.e. non-cellular communication systems.
Examples of such external wireless systems which can be located on
a cellular device or UE are LTE, WiFi, Bluetooth transceivers,
Global Navigation Satellite System (GNSS) receiver, sports or
medical related short range wireless devices, cordless telephone
etc. Examples of GNSS are Global Positioning System (GPS), Galileo,
Common Positioning. Architecture for Several Sensors (COMPASS),
Galileo and Additional Navigation Satellite Systems (GANSS)
etc.
There are a variety of user equipments and user equipments are
referred with different technical and brand names e.g. USB-dongle,
target device, mobile terminal, wireless terminal, wireless
terminal used for machine type communication, wireless device used
for device to device communication etc. FIG. 1 shows the 3GPP
frequency bands around 2.4 GHz industrial, scientific and medical
(ISM) bands. The transmit power of one transmitter may be much
higher than the received power level of another receiver, which due
to extreme proximity of these radio transceivers, can cause
interference on the victim radio receiver.
Wi-Fi uses frequency band 2400-2495 MHz in the ISM band. This band
is divided into 14 channels, where each channel has a bandwidth of
22 MHz, and 5 MHz separation from other channel with an exception
of channel number 14 where separation is 12 MHz. The transmitter of
LTE band 40 will affect receiver of WiFi and vice-versa. Since band
7 is a Frequency Division Duplexing (FDD) band so there is no
impact on LTE receiver from Wi-Fi transmitter but Wi-Fi receiver
will be affected by LTE Uplink (UL) transmitter. Bluetooth operates
between 2402-2480 MHz, in 79 channels of 1 MHz bandwidth each.
Therefore similar to Wi-Fi, there are interference between band 40
and Bluetooth as well as interference from band 7 UL to Bluetooth
Receiver (RX).
Furthermore, the reception of GNSS in the ISM band, e.g. Indian
Regional Navigation Satellite System that operates 2483.5-2500 MHz,
can be affected by band 7 UL transmission.
In summary some examples of interference scenarios are: LTE Band 40
radio transmitter (TX) causing interference to ISM radio RX ISM
radio TX causing interference to LTE Band 40 radio RX LTE Band 7
radio TX causing interference to ISM radio RX LTE Band 7/13/14
radio TX causing interference to GNSS radio RX
Note that the frequency bands and radio technologies discussed
above are just examples of different possible scenarios. In general
the interference can be caused by any radio technology and in any
neighboring or sub harmonic frequency band.
To avoid interference from LTE transceiver to other technologies,
some interference avoidance solutions can be used in the UE or by
the network. Interference avoidance solution can either be done
autonomously by the UE, or performed by the network based on an
indication from the UE.
In the following the two methods are briefly described:
When a UE experiences a level of In Device Coexistence (IDC)
interference that cannot be solved by the UE itself, the UE sends
an IDC indication via dedicated Radio Resource Control (RRC)
signaling to report the problems, so called Network-controlled
UE-assisted Interference avoidance. Indications can be sent by the
UE whenever it has problem in ISM DL reception, or in LTE DL
reception. Part of the IDC indication message is interference
direction, which indicates the direction of IDC interference. The
triggering of IDC indication is up to UE implementation, i.e. it
may rely on existing LTE measurements and/or UE internal
coordination.
The information element, InDeviceCoexIndication, defined in LTE RRC
specification, TS 36.331, Rel-11, v. 11.1.0 section 5.6.9 and also
shown below describes the message sent by the UE to the radio base
station when it experiences problem related to IDC.
The InDeviceCoexIndication message is used to inform E-UTRAN about
the IDC problems experienced by the UE, any changes in the IDC
problems previously informed, and to provide the E-UTRAN with
information in order to resolve them.
Signalling radio bearer: SRB1
RLC-SAP: AM
Logical channel: DCCH
Direction: UE to E-UTRAN
TABLE-US-00001 InDeviceCoexIndication message -- ASN1START
InDeviceCoexIndication-r11 ::= SEQUENCE { criticalExtensions CHOICE
{ c1 CHOICE { inDeviceCoexIndication-r11
InDeviceCoexIndication-r11-IEs, spare3 NULL, spare2 NULL, spare1
NULL }, criticalExtensionsFuture SEQUENCE { } } }
InDeviceCoexIndication-r11-IEs ::= SEQUENCE {
affectedCarrierFreqList-r11 AffectedCarrierFreqList-r11 OPTIONAL,
tdm-AssistanceInfo-r11 TDM-AssistanceInfo- r11 OPTIONAL,
lateNonCriticalExtension OCTET STRING OPTIONAL,
nonCriticalExtension SEQUENCE { } OPTIONAL }
AffectedCarrierFreqList-r11 ::= SEQUENCE (SIZE (1..maxFreqIDC-r11))
OF AffectedCarrierFreq-r11 AffectedCarrierFreq-r11 ::= SEQUENCE {
carrierFreq-r11 MeasObjectId, interferenceDirection-r11 ENUMERATED
{eutra, other, both, spare} } TDM-AssistanceInfo-r11 ::= CHOICE {
drx-AssistanceInfo-r11 SEQUENCE { drx-CycleLength-r11 ENUMERATED
{n1} OPTIONAL, drx-Offset-r11 ENUMERATED {n1} OPTIONAL,
drx-ActiveTime-r11 ENUMERATED {n1} OPTIONAL -- The above three
parameters (i.e. drx- cycleLength-r11, drx-Offset-r11 and --
drx-ActiveTime-r11) are FFS and need to be discussed },
idc-SubframePattern-r11 SEQUENCE { idc-SubframePatternList-r11 IDC-
SubframePatternList-r11 }, ... } IDC-SubframePatternList-r11 ::=
SEQUENCE (SIZE (1..maxSubframePatternIDC-r11)) OF IDC-
SubframePattern-r11 IDC-SubframePattern-r11 ::= CHOICE {
subframePatternFDD-r11 BIT STRING (SIZE (40)),
subframePatternTDD-r11 CHOICE { subframeConfig0-r11 BIT STRING
(SIZE (70)), subframeConfig1-5-r11 BIT STRING (SIZE (10)),
subframeConfig6-r11 BIT STRING (SIZE (60)) }, ... } -- ASN1STOP
When notified of IDC problems through an IDC indication from the
UE, the radio base station can choose to apply Frequency Division
Multiplexing (FDM) or Time Division Multiplexing (TDM)
solutions.
To assist the radio base station in selecting an appropriate
solution, all necessary/available assistance information for both
FDM and TDM solutions is sent together in the IDC indication to the
radio base station. The IDC indication is also used to update the
IDC assistance information, including for the cases when the UE no
longer suffers from IDC interference.
The two solutions are explained in more details in the
following:
The basic concept of an FDM solution is to move the LTE signal away
from the ISM band by performing inter-frequency handover within
E-UTRAN. The UE informs the network when operating LTE or other
radio signals would benefit or no longer benefit from LTE not using
certain carriers or frequency resources. By sending a list of
E-UTRA carrier frequencies affected by the IDC problem, the UE will
indicate which frequencies are unusable due to in-device
coexistence.
The basic concept of a TDM solution is to ensure that transmission
time of a radio signal does not coincide with reception time of
another radio signal of an external wireless system e.g. Wireless
Local Area Network (WLAN) or GNSS. The UE can signal the necessary
information, e.g. interferer type, mode, and possibly the
appropriate offset in subframes to the radio base station. The UE
can also signal a suggested pattern to the radio base station.
Based on such information, the final TDM patterns, i.e. scheduling
and unscheduled periods, are configured by the radio base
station.
The TDM solutions are divided into different types of methods:
Discontinuous Reception (DRX)-based solution: LTE DRX mechanism is
to provide TDM patterns to resolve the IDC issues. The TDM pattern
is specified by a total length called DRX periodicity and consists
of an active period, scheduling period, and an inactive period,
unscheduled period, as shown in FIG. 2. The UE provides the radio
base station with a desired TDM pattern consisting of periodicity
of the TDM pattern and scheduling period, or unscheduled period. It
is up to the network node to decide and signal the pattern that is
used by the UE.
All DRX definitions are according to 3GPP TS 36.321 section 3.1
v.11.0.0. The IDC indication message includes information related
to DRX cycle length which indicates the desired DRX cycle length
that the E-UTRAN is recommended to configure, DRX offset which
indicates the desired DRX starting offset that the E-UTRAN is
recommended to configure, and DRX active time which indicates the
desired active time that the E-UTRAN is recommended to configure.
Hybrid Automatic Repeat Request (HARQ) process reservation based
solution: In this TDM solution, a number of LTE HARQ processes or
subframes are reserved for LTE operation, and the remaining
subframes are used to accommodate ISM/GNSS traffic. FIG. 3 shows as
an example the HARQ reservation process for LTE Time Division
Duplexing (TDD) configuration 1, 3GPP TR 36.816 v. 11.2.0 Figure
5.2.1.2.2-1. In this way interference across in-device co-existing
systems can be avoided since UE does not transmit in certain
subframes during which it receives ISM/GNSS signals.
Subframe reservation pattern is sent to the UE in the form of a
bitmap based on the assistance information reported by the UE. The
provided bitmap is a list of one or more subframe patterns
indicating which HARQ process E-UTRAN is requested to abstain from
using. Value 0 indicates that E-UTRAN is requested to abstain from
using the subframe. As an example the bit sequence 1111110100 means
that subframes number 7, 9 and 10 must not be used. The size of bit
string for FDD is 40, and for TDD is 70, 10, 60 for subframe
configurations 0, 1-5, and 6, respectively. The key point here is
that the reserved subframes should comply with LTE release 8/9 UL
and DL HARQ timing.
The UE can also deny LTE subframes autonomously, to avoid
interfering with important signaling in other radio technologies.
During the denied subframes the UE does not transmit any signal. It
may also not receive any signal. The amount of denials is limited
using a maximum allowed denial subframes over a denial validity
period. Both the maximum denial subframes and the denial validity
period are configured by the radio base station. Configuring a
proper denial rate is left up to radio base station implementation,
but the UE decides which subframes are denied, without any further
feedback to the radio base station. That is why it is also called
as, `autonomous denials`. If the radio base station does not
configure any denial rate, the UE shall not perform any autonomous
denials.
The information element `IDC-Config` defined in LTE RRC
specification, TS 36.331, v. 11.1.0 section 6.3.6, and also shown
below describes the message sent by the E-UTRAN (eNB) to the UE to
release or setup autonomous denial parameters,
autonomousDenialSubframes and autonomousDenialValidity.
TABLE-US-00002 OtherConfig information element -- ASN1START
OtherConfig-r9 ::= SEQUENCE { reportProximityConfig-r9
ReportProximityConfig-r9 OPTIONAL,-- Need ON ... , [[
idc-Config-r11 IDC-Config-r11 OPTIONAL -- Need ON ]] }
IDC-Config-r11 ::= CHOICE { release NULL, setup SEQUENCE {
autonomousDenialParameters-r11 SEQUENCE {
autonomousDenialSubframes-r11 ENUMERATED {n2, n5, n10, n15, n20,
n30, spare2, spare1}, autonomousDenialValidity-r11 ENUMERATED
{sf200, sf500, sf1000, sf2000, spare4, spare3, spare2, spare1} }
OPTIONAL, -- Need OR ... } } ReportProximityConfig-r9 ::= SEQUENCE
{ proximityIndicationEUTRA-r9 ENUMERATED {enabled} OPTIONAL, --
Need OR proximityIndicationUTRA-r9 ENUMERATED {enabled} OPTIONAL --
Need OR } -- ASN1STOP
Radio Resource Management (RRM) Measurement
Several radio related measurements are used by the UE or the radio
network node to establish and keep the connection, as well as
ensuring the quality of a radio link.
The RRM measurements are used in RRC idle state operations such as
cell selection, cell reselection, e.g. between E-UTRANs, between
different Radio Access Technologies (RAT), and to non-3GPP RATs,
and minimization of drive test (MDT), and also in RRC connected
state operations such as for cell change, e.g. handover between
E-UTRANs, handover between different RATs, and handover to non-3GPP
RATs.
Cell ID Measurements
The UE has to first detect a cell and therefore cell identification
e.g. acquisition of a Physical Cell Identity (PCI), is also a
signal measurement. The UE may also have to acquire the Cell Global
ID (CGI) of a UE.
In HSPA and LTE the serving cell can request the UE to acquire the
System Information (SI) of the target cell. More specifically the
SI is read by the UE to acquire the CGI, which uniquely identifies
a cell, of the target cell. The UE also be requested to acquire
other information such as Closed Subscriber Group (CSG) indicator,
CSG proximity detection etc from the target cell.
The UE reads the SI of the target cell, e.g. intra-,
inter-frequency or inter-RAT cell, upon receiving an explicit
request from the serving network node via RRC signaling e.g. from
RNC in HSPA or eNode B in case of LTE. The acquired SI is then
reported to the serving cell. The signaling messages are defined in
the relevant HSPA and LTE specifications.
In order to acquire the SI which contains the CGI of the target
cell, the UE has to read at least part of the SI including master
information block (MIB) and the relevant system information block
(SIB) as described later. The terms SI
reading/decoding/acquisition, CGI/ECGI
reading/decoding/acquisition, CSG SI reading/decoding/acquisition
are interchangeably used but have the same or similar meaning. In
order to read the SI to obtain the CGI of a cell the UE is allowed
to create autonomous gaps during DL and also in UL. The autonomous
gaps are created for example at instances when the UE has to read
MIB and relevant SIBs of the cell, which depends upon the RAT. The
MIB and SIBs are repeated with certain periodicity. Each autonomous
gap is typically 3-5 ms in LTE and UE needs several of them to
acquire the CGI.
Signal Measurements
The Reference signal received power (RSRP) and Reference signal
received quality (RSRQ) are the two existing measurements used for
at least RRM such as for mobility, which include mobility in RRC
connected state as well as in RRC idle state. The RSRP and RSRQ are
also used for other purposes such as for enhanced cell ID
positioning, minimization of drive test etc.
The RSRP measurement provides cell-specific signal strength metric
at a UE. This measurement is used mainly to rank different LTE
candidate cells according to their signal strength and is used as
an input for handover and cell reselection decisions. Cell specific
Reference Signals (CRS) are used for RSRP measurement. These
reference symbols are inserted in the first and third last
Orthogonal Frequency Division Multiplexing (OFDM) symbol of each
slot, and with a frequency spacing of 6 subcarriers. Thus within a
resource block of 12 subcarriers and 0.5 ms slot, there are 4
reference symbols.
The RSRQ is a quality measure which is the ratio of the RSRP and
carrier Received Signal Strength Indicator (RSSI). The latter part
includes interference from all sources e.g. co-channel
interference, adjacent carriers, out of band emissions, noise
etc.
The UE depending upon its capability may also perform inter-RAT
measurements for measuring on other systems e.g. HSPA, GSM/GSM
Enhanced Data rate for GSM Evolution (EDGE) Radio Access Network
(GERAN), Code Division Multiple Access CDMA2000, 1.times.Round Trip
Time (RTT) and High Rate Packet Data (HRPD) etc. Examples of
inter-RAT radio measurements which can be performed by the UE are
Common Pilot Channel Received Signal Code Power (CPICH RSCP) and
CPICH energy per chip over total received power spectral density
(Ec/No) for inter-RAT UTRAN, GERAN carrier RSSI for inter-RAT GSM
and even pilot strength measurements for CDMA2000
1.times.RTT/HRPD.
In RRC connected state the UE can perform intra-frequency
measurements without measurement gaps. However as a general rule
the UE performs inter-frequency and inter-RAT measurements in
measurement gaps unless it is capable of performing them without
gaps. To enable inter-frequency and inter-RAT measurements for the
UE requiring gaps, the network has to configure the measurement
gaps. Two periodic measurement gap patterns both with a measurement
gap length of 6 ms are defined for LTE: Measurement gap pattern #0
with repetition period 40 ms Measurement gap pattern #1 with
repetition period 80 ms
The measurements performed by the UE are then reported to the
network, which may use them for various tasks.
The radio network node, e.g. radio base station, may also perform
signal measurements. Examples of radio network node measurements in
LTE are propagation delay between UE and itself, UL Signal to
Interference plus Noise Ratio (SINR), UL Signal to Noise Ratio
(SNR), UL signal strength, Received Interference Power (RIP) etc.
The radio base station may also perform positioning measurements
which are described in a later section.
Radio Link Monitoring Measurements
The UE also performs measurements on the serving cell (aka primary
cell) in order to monitor the serving cell performance. This is
called as Radio Link Monitoring (RLM) or RLM related measurements
in LTE.
For RLM the UE monitors the downlink link quality based on the
cell-specific reference signal in order to detect the downlink
radio link quality of the serving cell or Primary Cell (PCell).
In order to detect out of sync and in sync the UE compares the
estimated quality with the thresholds Qout and Qin respectively.
The threshold Qout and Qin are defined as the level at which the
downlink radio link cannot be reliably received and corresponds to
10% and 2% block error rate of a hypothetical Physical Downlink
Control Channel (PDCCH) transmissions respectively.
In non-DRX downlink link quality for out of sync and downlink link
quality for in sync are estimated over an evaluation periods of 200
ms and 100 ms respectively.
In DRX downlink link quality for out of sync and downlink link
quality for in sync are estimated over the same evaluation period,
which scale with the DRX cycle e.g. period equal to 20 DRX cycles
for DRX cycle greater than 10 ms and up to 40 ms.
In non-DRX the out of sync status and in sync status are assessed
by the UE in every radio frame. In DRX the out of sync status and
in sync status are assessed by the UE once every DRX.
In addition to filtering on physical layer, i.e. evaluation period,
the UE also applies higher layer filtering based on network
configured parameters. This increases the reliability of radio link
failure detection and thus avoids unnecessary radio link failure
and consequently RRC re-establishment. The higher layer filtering
for radio link failure and recovery detection would in general
comprise the following network controlled parameters: Hysteresis
counters e.g. N310 and N311 out of sync and in sync counters
respectively. Timers e.g. T310 Radio Link Failure (RLF) timer
For example the UE starts the timer T310 after N310 consecutive Out
of Sync (OOS) detections. The UE stops the timer T310 after N311
consecutive In sync (IS) detections. The transmitter power of the
UE is turned off within 40 ms after the expiry of T310 timer. Upon
expiry of T310 timer the UE starts T311 timer. Upon T311 expiry the
UE initiates RRC re-establishment phase during which it reselects a
new strongest cell.
In HSPA similar concept called out of sync and in sync detection
are carried out by the UE. The higher layer filtering parameters,
i.e. hysteresis counters and timers, are also used in HSPA. There
is also RLF and eventually RRC re-establishment procedures
specified in HSPA.
Sampling of Cell Measurement
The overall serving cell or neighbour cell measurement quantity
results comprise non-coherent averaging of 2 or more basic
non-coherent averaged samples. The exact sampling depends upon the
implementation and is generally not specified. An example of RSRP
measurement averaging in E-UTRAN is shown in FIG. 4. The FIG. 4
illustrates that the UE obtains the overall measurement quantity
result by collecting four non-coherent averaged samples or
snapshots, each of 3 ms length in this example, during the physical
layer measurement period, i.e. 200 ms, when no DRX is used or when
DRX cycle is not larger than 40 ms. Every coherent averaged sample
is 1 ms long. The measurement accuracy of the neighbour cell
measurement quantity, e.g. RSRP or RSRQ, is specified over this
physical layer measurement period. It should be noted that the
sampling rate is UE implementation specific. Therefore in another
implementation a UE may use only 3 snap shots over 200 ms interval.
Regardless of the sampling rate, it is important that the measured
quantity fulfils the performance requirements in terms of the
specified measurement accuracy.
In case of RSRQ both RSRP, numerator, and carrier RSSI,
denominator, should be sampled at the same time to follow similar
fading profile on both components. The sampling also depends upon
the length of the DRX cycle. For example for DRX cycle >40 ms,
the UE typically takes one sample every DRX cycle over the
measurement period.
A similar measurement sampling mechanism is used for other signal
measurements by the UE and also by the radio base station for UL
measurements.
HARQ in LTE
Hybrid Automatic Repeat Request (HARQ) is a process of
acknowledging the transmission in downlink or uplink. If the
received data is error-free an acknowledgement is sent to the
transmitter declaring a positive acknowledgement (ACK). If on the
other hand, error detected in the transmission, a negative
acknowledgement (NACK) is sent to the transmitter, which means that
the packet must be re-transmitted. In LTE, certain timing is agreed
between the transmitter and receiver for retransmissions.
In FDD mode, HARQ processes have 8 ms, 8 subframes, round trip time
in both UL and DL. This means that 4 ms after transmission an ACK
or NACK feedback is expected from the receiver, and if a
retransmission is required 4 ms after the feedback, the packet is
retransmitted.
In TDD mode since the DL and UL subframes can be different, in
different UL/DL configurations, the HARQ timing is different. As an
example in UL/DL configuration 1, as the table below shows, the
ACK/NACK feedback to a downlink transmission can only be sent on
subframes number 2, 3, 7, and 8. Therefore the 8 ms round trip time
that was mentioned for FDD, cannot be valid for this case.
TABLE-US-00003 TABLE 1 TDD Uplink-Downlink configurations Downlink-
to-Uplink Uplink- Switch- downlink point Subframe number
configuration periodicity 0 1 2 3 4 5 6 7 8 9 0 5 ms D S U U U D S
U U U 1 5 ms D S U U D D S U U D 2 5 ms D S U D D D S U D D 3 10 ms
D S U U U D D D D D 4 10 ms D S U U D D D D D D 5 10 ms D S U D D D
D D D D 6 5 ms D S U U U D S U U D
CSI Feedback
In order to utilize the variations in channel in the channel
dependent scheduling, LTE UE must provide the radio base station
with the channel state report. The channel state report is based on
known reference symbols that are transmitted in the DL. The channel
state report comprises one or several of the following information:
Rank indication (RI): RI is a recommendation to eNB, on how many
layers in the downlink transmission must be used. The RI is only
one value which means that the recommended rank is valid across the
whole bandwidth Precoder matrix indication (PMI): PMI indicates the
recommended precoder matrix that must be used in the downlink
transmission. The recommended precoder matrix can be
frequency-selective. Channel quality indication (CQI): CQI shows
the highest modulation and coding that can be used for DL
transmission. CQI can be frequency-selective too, which means that
multiple CQI reports can be sent for different parts of the
bandwidth.
LTE network can request both periodic and aperiodic CSI reports. In
LTE release 8/9 both periodic and aperiodic reports are based on
Cell-specific Reference Signal (CRS), but in LTE release 10, the
CSI report can also be based on CSI-RS which is used for
transmission mode 9.
Positioning
Several positioning methods for determining the location of the
target device, which can be any of the wireless device or UE,
mobile relay, Personal Digital Assistant (FDA) etc exist. The
position of the target device is determined by using one or more
positioning measurements, which can be performed by a suitable
measuring node or device. Depending upon the positioning the
measuring node can either be the target device itself, a separate
radio node, i.e. a standalone node, serving and/or neighboring node
of the target device etc. Also depending upon the positioning
method the measurements can be performed by one or more types of
measuring nodes.
The well-known positioning methods are: Satellite based methods: In
this case the measurements performed by the target device on
signals received from the navigational satellites are used for
determining target device's location. For example either GNSS or
A-GNSS, e.g. A-GPS, Galileo, COMPASS, GANSS etc, measurements are
used for determining the UE position Observed Time Difference Of
Arrival (OTDOA): This method uses UE measurement related to time
difference of arrival of signals from radio nodes, e.g. UE
Reference Signal Time Difference (RSTD) measurement, for
determining UE position in LTE or Single Frequency Network
(SFN)-SFN type 2 in HSPA. Uplink Time Difference Of Arrival
(UTDOA): It uses measurements done at a measuring node, e.g.
Location Measurement Unit (LMU), on signals transmitted by a UE.
The LMU measurement is used for determining the UE position.
Enhanced cell ID (E-CID): It uses one or more of measurements for
determining the UE position e.g. any combination of UE Rx-Tx time
difference, BS Rx-Tx time difference, timing advanced (TA) measured
by the radio base station, LTE RSRP/RSRQ, HSPA CPICH measurements,
CPICH RSCP/Ec/No, Angle of Arrival (AoA) measured by the radio base
station on UE transmitted signals etc for determining UE position.
The Time Advance measurement is done using use either UE Rx-Tx time
difference or BS Rx-Tx time difference or both. Hybrid methods: It
relies on measurements obtained using more than one positioning
method for determining the UE position
In LTE the positioning node, a.k.a. Evolved Serving Mobile Location
Centre (E-SMLC) or location server, configures the UE, radio base
station or LMU to perform one or more positioning measurements
depending upon the positioning method. The positioning measurements
are used by the UE or by a measuring node or by the positioning
node to determine the UE location. In LTE the positioning node
communicates with UE using LTE Positioning Protocol (LPP) protocol
and with radio base station using LTE Positioning Protocol annex
(LPPa) protocol.
Device-to-Device (D2D) Communication
D2D communication enables direct communication between devices e.g.
between pair or group of UEs. The D2D communication can be managed
by a radio network node or can be done autonomously by the UEs
involved in D2D communication. In the former case the D2D UEs
maintain a communication link also with the radio network node for
control, resource assignment etc. The D2D communication can share
the spectrum or frequency band used for cellular communication
between UE and radio network node or can use a dedicated spectrum
or band.
There are several motivations for introducing the possibility for
direct D2D communication as opposed to requiring devices to
communicate via an infrastructure node, such as a cellular base
station or a wireless access point.
The D2D UE performs the radio measurements, e.g. RSRP, RSRQ, UE
Rx-Tx time difference etc, like normal UE on signals transmitted to
and/or received from the radio network node. In addition the D2D UE
also performs the radio measurements on signals transmitted to
and/or received from the other D2D UE with which it communicates.
These D2D specific measurements are also similar to SINR, SNR,
Block Error Ratio (BLER), RSRP, RSRQ, UE Rx-Tx time difference
etc.
Measurements performed at a user equipment or a base station may
sometimes be inaccurate due to interferences from a different
technology used within the device and may degrade the performance
of the communications network.
SUMMARY
An object of embodiments herein is to provide a mechanism that
improves the accuracy of measurements performed in a communications
network.
According to an aspect the object is achieved by a method in a user
equipment for performing a radio measurement in a communications
network. The user equipment is In Device Coexistent, IDC, capable
and is served by a network node in the communications network. The
user equipment receives, from the network node, an IDC
configuration for at least one IDC scheme. The user equipment
further performs a radio measurement which meets one or more
requirements related to the radio measurement provided the received
IDC configuration meets a certain condition.
According to another aspect the object is achieved by a method in a
network node for enabling a user equipment to perform a radio
measurement in a communications network. The user equipment is IDC
capable and is served by the network node in the communications
network. The network node configures the user equipment with an IDC
configuration for at least one IDC scheme. The IDC configuration
enables the user equipment to perform a radio measurement which
meets one or more requirements related to the radio measurement
provided the IDC configuration meets a certain condition.
According to yet another aspect the object is achieved by a user
equipment adapted for performing a radio measurement in a
communications network. The user equipment is IDC capable and is
configured to be served by a network node in the communications
network. The user equipment comprises a receiver configured to
receive, from the network node, an IDC configuration for at least
one IDC scheme. The user equipment further comprises a performing
circuit configured to perform a radio measurement which meets one
or more requirements related to the radio measurement provided the
received IDC configuration meets a certain condition.
According to still another aspect the object is achieved by a
network node adapted for enabling a user equipment to perform a
radio measurement in a communications network. The user equipment
is IDC capable and the network node is configured to serve the user
equipment in the communications network. The network node comprises
a configuring circuit adapted to configure the user equipment with
an IDC configuration for at least one IDC scheme. The IDC
configuration enables the user equipment to perform a radio
measurement which meets one or more requirements related to the
radio measurement provided the IDC configuration meets a certain
condition.
In that the user equipment performs a radio measurement which meets
one or more requirements related to the radio measurement provided
the IDC configuration meets a certain condition, this improves the
accuracy of measurements performed in a communications network.
BRIEF DESCRIPTION OF THE DRAWINGS
Embodiments will now be described in more detail in relation to the
enclosed drawings, in which:
FIG. 1 shows 3GPP frequency bands around ISM band;
FIG. 2 shows DRX pattern for IDC interference avoidance;
FIG. 3 is an illustration of HARQ process reservation;
FIG. 4 shows an example of RSRP measurement averaging in
E-UTRAN,
FIG. 5 is a schematic overview depicting a radio communications
network according to embodiments herein;
FIG. 6 is a combined flow chart and signalling scheme depicting
embodiments herein;
FIG. 7 illustrates autonomous denial between the measurement
samples;
FIG. 8 illustrates the adjusting of the measurement instants to the
denial;
FIG. 9 shows a method of adjusting the denial period;
FIG. 10 shows a method of combination of adjusting the measurement
sampling and denial period;
FIG. 11 shows an example of adapting scheduling to IDC signal;
FIG. 12 is a schematic flow chart depicting a method in a user
equipment according to embodiments herein;
FIG. 13 is a block diagram depicting a user equipment according to
embodiments herein;
FIG. 14 is a schematic flow chart depicting a method in a network
node according to embodiments herein; and
FIG. 15 is a block diagram depicting a network node according to
embodiments herein.
DETAILED DESCRIPTION
FIG. 5 is a schematic overview depicting a communications network
1, e.g. a radio communications network. The communications network
1 comprises one or more RANs and one or more CNs and may use a
number of different technologies, such as LTE, LTE-Advanced,
Wideband Code Division Multiple Access (WCDMA), (GSM/EDGE),
Worldwide Interoperability for Microwave Access (WiMax), or Ultra
Mobile Broadband (UMB), just to mention a few possible
implementations.
In the communications network 1, a user equipment 10, also known as
a mobile station and/or a wireless terminal, communicates via a
Radio Access Network (RAN) to one or more core networks (CN). It
should be understood by the skilled in the art that "user
equipment" is a non-limiting term which means any wireless
terminal, Machine Type Communication (MTC) device or node e.g.
Personal Digital Assistant (PDA), laptop, mobile, sensor, relay,
mobile tablets or even a small base station communicating within a
cell.
The communications network 1 covers a geographical area which is
divided into cell areas, e.g. a cell 11 being served by a radio
base station 12. The radio base station 12 may also be referred to
as a first radio base station, a NodeB, an evolved Node B (eNB,
eNodeB), a base transceiver station, Access Point Base Station,
base station router, or any other network unit capable of
communicating with a user equipment within the cell served by the
radio base station depending e.g. on the radio access technology
and terminology used. The radio base station 12 may serve one or
more cells, such as the cell 11.
A cell is a geographical area where radio coverage is provided by
radio base station equipment at a base station site. The cell
definition may also incorporate frequency bands and radio access
technology used for transmissions, which means that two different
cells may cover the same geographical area but using different
frequency bands. Each cell is identified by an identity within the
local radio area, which is broadcast in the cell. Another identity
identifying the cell 11 uniquely in the whole communications
network 1 is also broadcasted in the cell 11. The radio base
station 12 communicates over the air or radio interface operating
on radio frequencies with the user equipment 10 within range of the
radio base station 12. The user equipment 10 transmits data over a
radio interface to the radio base station 12 in UL transmissions
and the radio base station 12 transmits data over the radio
interface to the user equipment 10 in Downlink (DL)
transmissions.
Furthermore, the communications network 1 comprises a core network
node such as a Positioning node 13 for enabling positioning of the
user equipment 10 or position related services. Another, a
different, or second, radio base station 14 is also comprised in
the communications network 1. The second radio base station 14
provides radio coverage over a second cell 15, another or a
different cell, e.g. a cell neighboring to the cell 11. The radio
base stations 12,14 and the positioning node 13 are all examples of
a network node. Other examples of a network node are a
Self-Organizing Network (SON) node, a Minimization of Drive Tests
(MDT) node or similar.
In some versions of the communications network 1, e.g. in UMTS,
several base stations are typically connected, e.g. by landlines or
microwave, to a controller node (not shown), such as a Radio
Network Controller (RNC) or a Base Station Controller (BSC), which
supervises and coordinates various activities of the plural base
stations connected thereto. The RNCs are typically connected to one
or more core networks. However, embodiments herein are exemplified
in an LTE network.
According to embodiments herein the user equipment 10 is In Device
Coexistence (IDC) capable, i.e. configured to avoid interference
between transmission and reception of different technologies in the
user equipment 10. When using interference avoidance solutions,
different measurements as described above, must satisfy the
measurement accuracies for the non-IDC case. In other words, an
interference avoidance solution must be transparent to the
measurements.
As explained earlier, when an interference avoidance solution is
used, some UL or DL subframes may be skipped by the user equipment
10. This can cause a lower accuracy since measurements are based on
a set of the received symbols. This may result in performance
degradation and may also cause measurement failure. In that the
user equipment 10 is IDC capable means that the user equipment 10
deals with the transmission (TX) and reception (RX) of signals to
and from one radio technology, such that it causes little or no
interference to other radio technologies in the same device, i.e.
the user equipment 10. Some IDC interference mitigation methods
require interrupting UL and/or DL operation in the user equipment
10 in one radio technology, to protect transceiver that is
operating in the other radio technology. This can have an impact on
the measurements that the user equipment 10 or the network node are
doing regularly. This in turn may degrade performance of the
communications network 1 since measurements are used for various
actions e.g. mobility, positioning etc. However, embodiments herein
suggest methods and apparatuses to ensure that the measurements
under IDC scenario are performed adequately.
Embodiments herein disclose methods to ensure that the user
equipment and/or a network node, exemplified herein as the radio
base station 12 or the positioning node 13, may perform
measurements that meet requirements when certain rules or
conditions are met. The methods comprise pre-defined rules and/or
pre-defined requirements. These rules and/or requirements may also
be applicable to the user equipment 10, which e.g. supports certain
frequency bands e.g. band 40, band 7 etc.
Examples of requirements, a.k.a. measurement requirements,
performance requirements etc., related to radio measurements are:
cell identification delay, CGI reporting delay, measurement period,
measurement reporting delay, measurement reporting time, UE
transmit timing accuracy, measurement accuracy, evaluation period
of out of sync in RLM, evaluation period of in sync in RLM, UE
transmit timing accuracy etc.
The requirements are also interchangeably called as performance
figures or performance requirements or measurement requirements
etc. The requirements depend upon the type of measurement,
procedure, e.g. handover, positioning, etc.
In order to meet any of the pre-defined requirements, the user
equipment 10 may have to adapt to one or more radio operations or
procedures, e.g. adaption of measurement sampling, adaptation of
autonomous denial subframes etc. A UE not adapting the radio
operations may not meet the pre-defined requirements which are
verified by conformance testing. Hence, these measurements are not
reliable and the performance of the communications network 1 would
be reduced. However, according to embodiments herein the network
node, e.g. the radio base station 12 the positioning node 13,
configures the user equipment 10 with an IDC configuration for at
least one IDC scheme, e.g. with an IDC subframe pattern, autonomous
denial parameters or similar. The IDC configuration enables the
user equipment 10 to perform a radio measurement which meets one or
more requirements related to the radio measurement provided the IDC
configuration meets a certain condition. Thus, the user equipment
10 receives, from the network node, the IDC configuration for the
at least one IDC scheme. The user equipment 10 then performs a
radio measurement which meets one or more requirements related to
the radio measurement provided the received IDC configuration meets
a certain condition. By configuring the user equipment 10 with an
IDC configuration that meets the certain condition, such as "less
than X denial subframes over a Transmission Time Interval (TTI)",
and only then the radio measurement may meet the requirement,
ensures that the measurement is reliable.
FIG. 6 is a schematic combined flow chart and signalling scheme
depicting some embodiments herein for performing a radio
measurement in the communications network 1. The user equipment 10
is capable of IDC handling and is served by the network node,
exemplified in the FIG. 6 as the radio base station 12, in the
communications network 1. The actions do not have to be taken in
the order stated below, but may be taken in any suitable order.
Action 600.
The radio base station 12 may determine on-going radio processes or
radio processes that are expected to start, which radio processes
are associated with the user equipment 10.
Action 601.
The user equipment 10 may report its capability to handle IDC to
the radio base station 12. The capability indicates that the user
equipment 10 is capable of performing a radio measurement which
meets one or more requirements related to the radio measurement
provided the IDC configuration meets a certain condition. According
to some embodiments the user equipment 10 indicates or provides
relevant capability information to the radio base station 12 to
inform the radio base station 12 whether the user equipment 10 is
capable of adapting one or more radio procedures, meeting
pre-defined rules and pre-defined requirements when it is
configured with one or more IDC scenario disclosed in preceding
sections.
The capability information sent to the radio base station 12 may
also contain additional or specific information e.g.: information
indicating whether the user equipment 10 is capable of adapting one
or more radio procedures and/or meeting rules and requirements
disclosed above only in specific IDC scenarios, e.g. when certain
external wireless system is GNSS co-existing with cellular;
information indicating whether the user equipment 10 is capable of
adapting one or more radio procedures and/or meeting rules and
requirements disclosed above only for certain frequency bands e.g.
LTE band 40, LTE band 7 etc.; information indicating whether the
user equipment 10 is capable of adapting one or more radio
procedures and/or meeting rules and requirements disclosed above
only for specific IDC solution e.g. autonomous denial, HARQ process
reservation based solution, DRX based solution etc; information
indicating whether the user equipment 10 is capable of adapting one
or more radio procedures and/or meeting rules and requirements
disclosed in preceding section also when in D2D communication mode;
Indicating whether the user equipment 10 is capable of adapting one
or more radio procedures and/or meeting rules and requirements
disclosed in preceding section only when operating in single
carrier mode; information indicating whether the user equipment 10
is capable of adapting one or more radio procedures and/or meeting
rules and requirements disclosed above only when operating in
single carrier mode; information indicating whether the user
equipment 10 is capable of adapting one or more radio procedures
and/or meeting rules and requirements disclosed above also when
operating in multi-carrier operational mode. It may also indicate
whether it can adapt one or more procedures for UL and/or DL
multi-carrier operation. Yet certain UEs may also indicate that
they are only capable of adapting one or more radio procedures
and/or meeting rules and requirements disclosed above in certain
type of multi-carrier operation e.g. intra-band contiguous Carrier
Aggregation (CA), inter-band CA, intra-band non-contiguous CA
etc.
The user equipment 10 may send the capability information, i.e.
related to the supported scheme, to the radio base station 12 in
any of the following manner: proactive reporting without receiving
any explicit request from radio base station 12 being e.g. serving
network node or any target network node such as the second radio
base station 14; reporting upon receiving any explicit request from
the radio base station 12 being e.g. serving network node or any
target network node such as the second radio base station 14. The
explicit request may be sent to the user equipment 10 by the
network anytime or at any specific occasion. For example the
request for the capability reporting may be sent to the user
equipment 10 during initial setup or after a cell change, e.g.
handover, RRC connection re-establishment, RRC connection release
with redirection, PCell change in CA, Primary Component Carrier
(PCC) change in PCC etc.
In case of proactive reporting the user equipment 10 may report its
capability during one or more of the following occasions: During
initial setup or call setup e.g. when establishing the RRC
connection; During cell change e.g. handover, primary carrier
change in multi-carrier operation, PCell change in multi-carrier
operation, RRC re-establishment, RRC connection release with
redirection etc.
Action 602.
The radio base station 12 determines IDC configuration for the user
equipment 10 based on for example the received capability. Thus,
the IDC configuration may be based on the received capability. The
radio base station 12 may determine the IDC configuration according
to a rule that will ensure consistent user equipment behaviour
and/or will ensure that the user equipment 10 meets one or more
requirements related to the radio measurement.
Action 603.
The radio base station 12 configures the user equipment 10 with the
IDC configuration for at least one IDC scheme, which IDC
configuration, as determined above, enables the user equipment 10
to perform a radio measurement which meets one or more requirements
related to the radio measurement provided the IDC configuration
meets the certain condition. Thus, the user equipment 10 receives,
from the radio base station 12 or another network node, the IDC
configuration for at least one IDC scheme. As exemplified, the
radio base station 12 may transmit the IDC configuration for at
least one IDC scheme to the user equipment 10.
Action 604.
The user equipment 10 may determine that the received IDC
configuration meets the certain condition. E.g. that the number of
denial subframes does not exceed a preset number of denial
subframes within a certain time interval.
Action 605.
The user equipment 10 may then perform a radio measurement which
meets one or more requirements related to the radio measurement
provided the received IDC configuration meets the certain
condition.
As mentioned earlier both the user equipment 10 and the radio base
station 12 are doing radio measurements regularly and based on
multiple received samples in time. When the user equipment 10
denies some sub-frames autonomously, the radio measurement may be
done based on a smaller number of samples. The radio measurement
has to meet certain pre-defined requirement such as measurement
accuracy over the measurement period a.k.a. physical layer (L1)
measurement period. For example RSRP is a measurement over 200 ms
in non-DRX and is required to meet certain measurement accuracy
e.g. .+-.6 dB with 90%-ile confidence interval. This means that due
to inadequate number of samples due to puncturing of certain
subframes or time instances the accuracy of the ongoing measurement
cannot be guaranteed. Note that the denial can be on both DL and UL
subframes, which impacts measurements at the user equipment 10 and
the radio base station 12, respectively. This also affects the user
equipment 10 and/or radio network node measurements which are done
on transmitted signals. For example BS Rx-Tx time difference is
measured on base station transmitted and user equipment transmitted
signals. Therefore in subframes or time instances in which the user
equipment 10 does not transmit due to autonomous denials the radio
base station 12 cannot perform BS Rx-Tx time difference
measurement.
Several examples of pre-defined rules and/or requirements are
provided below. The user equipment 10 and/or the radio base station
12 depending upon the rule/requirements may be required to meet one
or more of them.
For example it may be pre-defined that the user equipment 10 shall
meet one or more requirements related to measurements provided
certain conditions are met. Examples of conditions are: Values of
parameters related to a particular "interference avoidance
solution" e.g. DRX based solution, HARQ process reservation based
solution, UE autonomous solution based on denials etc. Examples of
requirements as mentioned earlier are measurement period,
evaluation periods used in RLM, out of sync and in sync in DRX and
in non DRX etc. For example it may be pre-defined that requirements
shall be met when the user equipment 10 is configured by the
network with an IDC configuration using certain range of parameters
e.g. when autonomous denial related parameter,
"autonomousDenialSubframes" is not larger than 20 ms, and/or when
autonomous denial related parameter, "autonomousDenialValidity" is
not larger than 1 second; or when autonomous denial related
parameter, "autonomousDenialSubframes" is up to full range, e.g. 30
ms, or any value; and/or when autonomous denial related parameter,
"autonomousDenialValidity" is up to full range, e.g. 2 s, or any
value. More specifically it may be pre-defined that the user
equipment 10 shall meet one or more requirements provided the user
equipment 10 is configured by the network with an IDC configuration
comprising of autonomousDenialSubframes not larger than certain
value, e.g. 20 ms, over certain autonomousDenialValidity duration,
e.g. 1 second.
In yet another specific example it may be pre-defined that
requirements, e.g. evaluation periods used in RLM out of sync and
in sync in DRX and in non DRX etc, shall be met by the user
equipment 10 when the user equipment 10 is configured by the
network with certain IDC subframe pattern, e.g. used for "HARQ
process reservation based solution", or using certain range of
parameters e.g. IDC subframe pattern configured by the network
comprises at least certain subframes per time period, e.g. per
frame, are available for usage by the user equipment 10 for E-UTRAN
e.g. certain number of `1` in every frame in an IDC pattern; IDC
subframe pattern configured by the network comprises at least one
subframe per per radio frame, are available for E-UTRAN usage by
the user equipment 10 or in other words in at least one out of ten
subframes the E-UTRAN is not required to abstain from using the
subframe. Example of such pattern is: [1000000000, 1000000000,
1000000000, 1000000000].
In some further embodiments it may be pre-defined that second set
of requirements shall be met by the user equipment 10 when the user
equipment 10 is configured by the network, e.g. the radio base
station 12, with a certain IDC related scheme otherwise the user
equipment 10 shall meet the first set of requirements. The second
set of requirements is more relaxed than the first set of
requirements. For example the second set of requirements can be
characterized with a longer measurement period than that used in
first set of requirements e.g. second and first set may use 400 ms
and 200 ms of measurement period respectively. For example it may
be pre-defined that the user equipment 10 shall perform a certain
measurement, e.g. RLM out of sync and/or in-sync, also when
configured with one or more IDC scheme, e.g. with an IDC subframe
pattern, autonomous denial parameters etc, however in this case the
measurement period, e.g. out of sync and/or in sync RLM evaluation
periods, of the said measurement may be extended compared to the
case when IDC is not configured.
In another example the measurement period may be the same, i.e. 200
ms, as without IDC gaps but another one or more pre-defined
requirements can be relaxed; for instance the number of identified
cells, i.e. no of RSRP/RSRQ measurements, required to be measured
by the user equipment 10 is reduced e.g. from 8 cells to 6 cells.
The exact reduction of cells can be governed by an expression which
is a function of the active or available time when the UE receiver
is guaranteed to be active for doing measurement. This is because
the available radio time for the user equipment 10 to do the
measurement is reduced proportional to the time of the IDC gaps,
i.e. idle time created by one or more TDM solution e.g. autonomous
denial, HARQ process reservation based solution etc.
The rule may be applicable only for certain measurements and/or for
certain pre-defined requirements or for all.
For example it may be pre-defined that the second set of
requirements shall be met by the user equipment 10 under certain
conditions e.g. when the user equipment 10 is configured by the
network with: IDC subframe pattern, e.g. used for "HARQ process
reservation based solution", and/or with autonomous denial
parameters, e.g. autonomousDenialValidity,
autonomousDenialSubframes etc.
More specifically it may be pre-defined that the second set of
requirements, or certain set of requirements, shall be met by the
user equipment 10 when the user equipment 10 is configured by the
network with: certain pattern of the IDC subframe pattern, e.g.
used for "HARQ process reservation based solution", e.g. 2 subframe
every 20 ms available for LTE operation. and/or with certain
parameter values associated with autonomous denial parameters, e.g.
autonomousDenialValidity >1 second, autonomousDenialSubframes
>20 ms etc.
According to another example of embodiments one or more rules are
pre-defined to set the priority between measurement gaps used by
the user equipment 10 for performing a radio measurement and gaps
created due to IDC operation, e.g. HARQ process reservation based
solution, autonomous denial etc, when both are simultaneously
configured or used by the user equipment 10. The problem may arise
especially if the type types of gaps overlap partially or fully.
The measurement gaps can be network configured gaps and/or the
measurement gaps can be UE autonomous gaps, e.g. for reading CGI of
a cell. The pre-defined rules will ensure consistent UE behavior
and will enable network to know the expected results from the user
equipment 10 according to the rule and if necessary enable network
to take necessary action.
Few specific examples are provided below: In one example a
pre-defined rule specifies that when the user equipment is
configured by the network with one or more IDC related schemes and
when the user equipment 10 is also requested to perform a
measurement using measurement gap then the user equipment 10 shall
prioritize the gaps or idle time created for the IDC over the
measurement gaps, i.e. overrides the gaps or idle time created for
the IDC over the measurement gaps. That means in this case the user
equipment 10 will not perform measurement during gaps and instead
creates gaps for IDC to avoid interference towards the in-device
external wireless system. It may also be specified that gaps or
idle time created for the IDC are prioritized by the user equipment
10 only when they partly or fully overlap with the measurement
gaps. In a second example, which is opposite to the previous one, a
pre-defined rule specifies that when the user equipment 10 is
configured by the network with one or more IDC related schemes and
when the user equipment 10 is also requested to perform a
measurement using measurement gap then the user equipment 10 shall
prioritize the measurement gaps over the gaps or idle time created
for the IDC, i.e. overrides the measurement gaps over the gaps or
idle time created for the IDC. That means in this case the user
equipment 10 will perform measurement during measurement gaps and
will not create idle gaps for IDC to avoid interference towards the
in-device external wireless system. It may also be specified that
measurement gaps are prioritized by the user equipment 10 only when
the measurement gaps partly or fully overlap with the gaps or idle
time created for the IDC.
It may also be pre-defined that the user equipment 10 shall meet
the requirements related to measurements performed in measurement
gaps, e.g. network configured gaps, autonomous gaps etc, provided
the measurement gaps do not overlap with idle time or gaps created
due to IDC configuration, e.g. IDC subframe pattern, autonomous
denial configurations etc. Examples of measurements done in gaps
are inter-frequency, inter-RAT etc. In order to meet this condition
the radio base station 12 configuring measurement gaps or
configuring a measurement which requires gaps, e.g. cell's CGI
acquisition, will be required to configure the measurement(s) which
need gaps and the IDC such that measurement gaps don't overlap or
collide with the idle time or gaps due to IDC. For example the
radio base station 12 may either postpone the measurements which
require gaps or it may postpone the IDC configuration. The decision
determining which one to postpone depends upon the scenario. For
example if an important measurement, e.g. measurement for handover
due to risk of handover failure, positioning for emergency call
etc, is required then the radio base station 12 may prioritize
configuring measurements requiring gaps over the IDC.
In prior art the priority level between gaps or idle time created
for the IDC and measurement gaps is not defined. This leads to
inconsistent UE behavior and may result in both IDC interference
and also failure of measurements in gaps. The radio base station 12
may also configure the user equipment 10 with both IDC scheme, i.e.
allow gaps for IDC, and measurement gaps for measurements. This
also increases signaling overheads, increases processing and
complexity at the user equipment 10.
According to another embodiment a rule or condition may be
pre-defined that when IDC gaps are created, e.g. when any of IDC
schemes is configured, the user equipment 10 shall meet positioning
measurement requirements provided the IDC gaps don't fully or at
least partly overlap or collide with the reference signals on which
positioning measurements are performed.
Examples of positioning measurements are OTDOA RSTD intra-frequency
RSTD measurement, inter-frequency RSTD measurement etc. Yet another
example is UL Time Difference of Arrival (UTDOA) measurements e.g.
UL Relative Time of Arrival (RTOA). The corresponding requirements
are RSTD measurement period, RSTD measurement accuracy, RTOA
measurement period etc.
To enable RSTD measurements the Positioning Reference Signal (PRS)
are configured with certain periodicity e.g. one PRS occasion can
carry up to 7 DL subframes with PRS with certain PRS occasion
periodicity, e.g. one occasion every 640 ms, 1280 ms etc.
Similarly for RTOA measurements done by the LMU, the user equipment
is configured with Sounding Reference Signal (SRS) with a certain
periodicity. For example if IDC scheme is configured in a way that
the IDC gaps don't overlap with PRS then user equipment 10 shall
meet the OTDOA RSTD requirements. In another example IDC gaps and
PRS subframes partially overlap then the user equipment 10 also
meets the RSTD requirements but only for the number of PRS
subframes which are available for the RSTD measurements in a PRS
occasion.
In order to ensure that the positioning measurements are performed
successfully by the user equipment 10, the network, i.e. the
network node, may ensure that one or more IDC scheme is configured
with parameters, e.g. IDC subframe pattern, autonomous denial
parameters etc, that the IDC gaps don't overlap or at least don't
fully overlap with the reference signals used for positioning.
Action 606.
In some embodiments, the radio base station 12 performs one or more
radio operation tasks or actions, such as type of measurement or
similar, based on the received capability. The acquired capability
information may be used by the radio base station 12 for performing
one or more radio operation tasks or actions. The tasks comprise
selection of a procedure, adapting a parameter in a configuration
message related to measurement, scheduling, mobility etc. One
example of radio operation task is the decision at the radio base
station 12 whether to configure the user equipment 10 to perform
certain type of measurement or not. For example depending upon the
capability the radio base station 12 may select an alternative
which is most suitable. For example if the user equipment 10
supports adaptation of procedures only under autonomous denial then
the network will use this method and also configure the user
equipment 10 to perform certain measurements. For other methods,
e.g. HARQ based solution, the network may either not use it when
critical measurements are to be performed by the user equipment 10
and/or by the radio base station 12. In yet another example the
user equipment 10 may use this scheme, HARQ based solution, but it
may not configure user equipment 10 to perform critical
measurements e.g. used for positioning in emergency situation.
Autonomous denial can be applied by the user equipment 10 based on
the parameters related to one or more radio measurements. For
example the adaptation of the autonomous denial may depend upon
parameters such as measurement period, number of measurement
samples, measurement sampling rate, measurement sample size etc
used for performing a radio measurement. If an autonomous denial
subframe period 71 is smaller than measurement sampling period, the
user equipment 10 can deny subframes in between the measurements
instants as shown in FIG. 7. For example, assume the measurement
sampling rate T comprises one 2 ms long measurement sample obtained
by the user equipment 10 every 40 ms. Also assume that the required
amount of total denials in terms of number of subframes is 30
subframes. Therefore the user equipment 10 may adapt the autonomous
denial such that it does not coincide with the measurement sampling
instances rather it falls within the successive measurement
samples. This way the samples that are used for the measurements
are saved and the accuracy of measurement is not impacted. This
also ensures that the user equipment 10 can meet the measurement
accuracy of the on-going measurement over the existing measurement
period without extending the measurement period. Therefore
performance of the measurement is not degraded and the
corresponding function such as handover which relies on measurement
is not degraded.
The user equipment 10 may adapt its autonomous denials thereby
avoiding collision between autonomously denied subframes, i.e. gaps
with no transmission and/or reception, with the measurement samples
and thus avoiding deteriorating the measurement performance.
If the number of subframes that the user equipment 10 denies is
larger than the measurement sampling period, the user equipment 10
may adjust the sampling to ensure measurement accuracy. Hence, some
embodiments herein disclose adjusting sampling time for the
measurements based on the denial subframe period. In the example
shown in FIG. 8, a second sampling instant 81 is delayed, T.sub.1,
so that it occurs after the denial period 82 is over. Previously a
UE performs sampling periodically i.e. samples are placed at
equidistance in time. Therefore according to this embodiment the
user equipment 10 will be required to obtain at least certain
measurement samples aperiodically. For example if the denial period
82 is 30 ms but the measurement sampling rate is 1 sample every ms,
then the user equipment 10 will not take any measurement sample
which would overlap with the denial period 82 and instead will take
one or more sample more frequently e.g. once every 10 ms, T2, after
the denial period 82 is over. This type of adaptation of
measurement sampling can be done either before or after the denial
period 82.
FIG. 9 discloses embodiments adjusting the denial period without
affecting the sampling time T of the measurements in case the
aggregated denial period is larger than the time between the
successive measurement sampling instances. This is particularly
useful in case the aggregated denial period is much larger than the
sampling period. In this case if the user equipment 10 follows the
method described in previous embodiment the user equipment 10 might
be required to perform adjustment of several samples. To elaborate
this embodiment consider that the total required denial period is
20 ms whereas the measurement sampling period is 10 ms e.g. 1 ms
sample is taken once every 10 ms. Using this embodiment the user
equipment 10 may split its denial period into 4 groups, Denial
period-1-Denial period-4, each of a time interval T of 5 ms and
create each one of them between the successive measurement samples.
This is illustrated in FIG. 9.
According to yet another aspect of embodiments herein the user
equipment may also apply the combination of the methods of
adjusting the sampling time period, i.e. shown in FIG. 8, and the
method of adjusting the denial period, shown in FIG. 9. The method
of combining adjustments of measurement sampling and denial period
is shown in FIG. 10. For example the user equipment 10 may split
the total denial subframes into 3 groups, Denial period-1-Denial
period-3: one of 10 ms which will require the user equipment 10 to
adjust the measurement sample and the remaining two each of 5 ms
which can be placed between successive measurement samples.
After performing one or more measurement according to any of the
adaption scheme described the user equipment 10 will use the
performed measurements for one or more radio operational tasks;
examples of such tasks are cell selection, cell reselection,
reporting measurement results to the network node which may use it
for mobility, positioning etc. The user equipment 10 may also
additionally report to the network that it has adapted or adjusted
any of the denial time, measurement sampling rate or combination
thereof.
Examples of radio operations at the network node which can be
adapted are scheduling of data, performing measurements, sending
measurement request etc. As an example, if the maximum number of
denials in the validity period is consumed, then the network node
or D2D UE can schedule the user equipment 10, i.e. UE1 in case of
D2D UE, for the remaining part of the validity without worrying
about any subframe denial. Also if a large number of denials are
used in a period, then the network node can schedule more
aggressively for the remaining part of the validity range e.g.
continuously if there is more data to send to the user equipment
10.
In yet another example a radio measurement can be done over the
entire remaining period 1101 of the validity period as shown in
FIG. 11. For example measurement period may have to be extended if
measurement is done in the initial 200 ms, but no extension is
required if done in remaining 800 ms.
In the preceding sections the methods related to adaption of one or
more procedures, e.g. measurement sampling, IDC configuration etc,
in an IDC scenario are described for the UE autonomous denial. The
UE autonomous denial is one of the TDM schemes used in IDC
scenario, i.e. when a cellular system, e.g. LTE band 40, and
external wireless system, e.g. ISM band, co-exist on the same
wireless device. However in principle the methods disclosed in
preceding disclosure are applicable to any type of TDM scheme in
which the user equipment does not operate, receive and/or transmit,
in certain subframes for cellular communication and instead use
that time for external wireless systems, e.g. GPS, WLAN etc. For
example in other TDM scheme related to IDC scenario such as in
"HARQ process reservation based solution" a number of LTE HARQ
processes or subframes are reserved for LTE operation and the
remaining subframes are used to accommodate the external wireless
system, e.g. ISM/GNSS traffic. The actual number of subframes
available for LTE operation and subframes available for the
external wireless system operation are allocated by the network.
More specifically the "HARQ process reservation based solution" is
realized by the network by configuring a pattern of subframes
called, "IDC subframe pattern" defined in TS 36.331 Rel-11, v.
11.1.0 sections 5.6.9 and 6.2.1. It defines the subframes for
external wireless system and for LTE usage. The pattern is e.g. of
40 ms for FDD and 70, 10 and 60 ms for LTE TDD. In other words the
user equipment 10 may have limited subframes for transmission
and/or reception of LTE signals. Therefore when network uses HARQ
process reservation based solution the user equipment 10 and/or the
network node, which may also cover a D2D UE, may also adapt the
radio procedures according to the rules described above. This in
turn will enable the user equipment 10 and the network node to meet
the pre-defined requirements and ensure good performance when IDC
scenario is operational. The methods also apply to DRX based
solution used in IDC scenario.
Method of Avoiding IDC Gaps During Critical Instances
In certain critical scenarios the network node may not configure
IDC scheme and/or the user equipment 10 may not send IDC request to
the network and/or the user equipment 10 may not create IDC gaps if
the user equipment 10 is configured with any of the IDC scheme,
e.g. IDC subframe pattern, autonomous denial parameters etc. Thus,
avoiding IDC gaps during critical instances. For example the user
equipment 10 may wait sending request or applying the IDC gaps
until the critical scenario or condition is over. Examples of
critical scenarios are: when user equipment 10 is scheduled to
receive and/or transmit with a high priority data, services, delay
stringent service (e.g. VOIP) etc. when the user equipment 10 is in
critical state e.g. on-going emergency calls, emergency positioning
session etc.
The critical scenarios in which the IDC gaps are not created or IDC
scheme is not configured can either be pre-defined and/or can be
informed by the network to the user equipment 10.
The method actions in the user equipment 10 for performing a radio
measurement in the communications network according to some
embodiments will now be described with reference to a flowchart
depicted in FIG. 12. The actions do not have to be taken in the
order stated below, but may be taken in any suitable order. Actions
performed in some embodiments are marked with dashed boxes.
Action 1201.
The user equipment 10 may report capability of the user equipment
10 to the network node 10. The capability indicates that the user
equipment 10 is capable of performing a radio measurement which
meets one or more requirements related to the radio measurement
provided the IDC configuration meets a certain condition
Action 1202.
The user equipment 10 receives, from the network node, the IDC
configuration for at least one IDC scheme.
Action 1203.
The user equipment 10 may determine that the received IDC
configuration meets the certain condition. E.g. the IDC autonomous
denial parameters comprises that not more than M IDC autonomous
denial subframes are configured over certain IDC autonomous denial
validity period. The certain range of parameters may comprise a
certain IDC subframe pattern. The certain range of parameters
comprises that at least M number of subframes are available for
E-UTRAN operation over a certain time period. The certain range of
parameters may comprise a list of one or more subframe patterns
indicating which Hybrid Automatic Repeat Request, HARQ, process
Evolved Universal Terrestrial Radio Access Network, E-UTRAN, is
required to abstain from using.
Action 1204.
The user equipment 10 performs a radio measurement which meets one
or more requirements related to the radio measurement provided the
received IDC configuration meets a certain condition. The certain
condition may comprise that the received IDC configuration
comprises a certain range of parameters. The certain range of
parameters may comprise certain IDC autonomous denial parameters.
Examples of IDC autonomous denial parameters are
autonomousDenialSubframes and autonomousDenialValidity.
In order to perform the method a user equipment is provided. FIG.
13 shows a user equipment 10 according to embodiments herein. The
user equipment 10 is adapted for performing a radio measurement in
the communications network 1. The user equipment 10 is IDC capable
and is configured to be served by the network node in the
communications network.
The user equipment 10 comprises a receiver (RX) 1301 configured to
receive, from the network node, the IDC configuration for at least
one IDC scheme.
The user equipment 10 further comprises a performing circuit 1302
configured to perform a radio measurement which meets one or more
requirements related to the radio measurement provided the received
IDC configuration meets a certain condition. The certain condition
may comprise that the received IDC configuration comprises a
certain range of parameters. The certain range of parameters may
e.g. comprise certain IDC autonomous denial parameters. The IDC
autonomous denial parameters may comprise that not more than M IDC
autonomous denial subframes are configured over certain IDC
autonomous denial validity period. In some embodiments, the certain
range of parameters comprises certain IDC subframe pattern. The
certain range of parameters may comprise that at least M number of
subframes are available for E-UTRAN operation over certain time
period. The certain range of parameters may comprise a list of one
or more subframe patterns indicating which HARQ process E-UTRAN is
required to abstain from using.
The user equipment 10 may further comprise a determining circuit
1303 configured to determine that the received IDC configuration
meets the certain condition.
In addition, the user equipment 10 may comprise a reporting circuit
1304 configured to report capability of the user equipment 10 to
the network node, e.g. by transmitting a report of capability to
the network node. The capability indicates that the user equipment
10 is capable of performing a radio measurement which meets one or
more requirements related to the radio measurement provided the IDC
configuration meets the certain condition.
Furthermore, the user equipment 10 comprises a transmitter (TX)
1305. The transmitter 1305 and receiver 1301 may be implemented as
a transceiver in the user equipment 10.
The embodiments herein for performing a radio measurement in the
communications network 1 may be implemented through one or more
processors, such as a processing circuit 1306 in the user equipment
10 depicted in FIG. 13, together with computer program code for
performing the functions and/or method steps of the embodiments
herein. The program code mentioned above may also be provided as a
computer program product, for instance in the form of a data
carrier carrying computer program code for performing embodiments
herein when being loaded into the user equipment 10. One such
carrier may be in the form of a CD ROM disc. It is however feasible
with other data carriers such as a memory stick. The computer
program code may furthermore be provided as pure program code on a
server and downloaded to the user equipment 10.
The user equipment 10 further comprises a memory 1307 that may
comprise one or more memory units and may be used to store for
example data such as, conditions, requirements, measurements,
capability an application to perform the methods herein when being
executed on the user equipment or similar.
According to one variant a method implemented in the user equipment
10 is provided, to determine when an autonomous denial can be
applied based on measurement time is provided, the method
comprising: a) Determining the conditions for the measurements at
the user equipment 10; b) Adapting the autonomous denial time, if
the requirements are met.
According to a further variant the user equipment 10 is provided,
comprising a processor and memory devices configured to determine
when an autonomous denial can be applied based on measurement time
is provided, the processor is further configured to: a) Determining
the conditions for the measurements at the user equipment 10; b)
Adapting the autonomous denial time, if the requirements are
met.
According to a further variant a method implemented in the user
equipment to adjust the sampling time for radio measurements based
on the inactivity period in the DL or UL time is provided.
The method actions in the network node, referred to as radio base
station 12 and/or positioning node 13 in the figures, may also be a
D2D user equipment, for enabling the user equipment 10 to perform a
radio measurement in the communications network according to some
embodiments will now be described with reference to a flowchart
depicted in FIG. 14. The actions do not have to be taken in the
order stated below, but may be taken in any suitable order. Actions
performed in some embodiments are marked with dashed boxes.
Action 1401.
The network node may determine on-going radio operations or radio
operations expected to start and the network node may then in
action 1404 below take the on-going radio operations into account
when configuring the user equipment 10.
According to some embodiments herein a method in the network node
to determine the allowed denial time by the user equipment 10 based
on one or more radio operations which are on-going or which are
expected to start is disclosed. Examples of radio operations are
radio measurements performed by the user equipment 10 and/or radio
network, scheduling of data, e.g. higher priority data, criticality
level of the on-going service, e.g. emergency call, positioning
session, etc.
As explained earlier, the network node, e.g. serving eNode B,
indicates the maximum number of autonomously denied subframes and
the validity period over which the denied subframes are
counted.
According to the some embodiments if there is one or more on-going
radio operations or if they are about to start then the serving
radio node serving the user equipment 10 adapts the IDC
configuration sent to the user equipment 10. The ID configuration
includes parameters such as autonomous denial subframes and the
autonomous denial validity fields. The adaptation of IDC
configuration which takes into account one or more radio operations
comprises one or more of the following, but not limited to these
examples: Sending the IDC configuration with certain delay: For
example this may be sent with the delay when the network node
and/or the user equipment 10 has completed the on-going radio
operation. The delay depends upon the type of radio operations e.g.
scheduling of data, measurement, positioning session etc. A shorter
delay, e.g. 10 ms, might be needed in case the operation task is
scheduling the data. That means the network node first schedule all
or most of the data and then send IDC configuration to allow the
denials. However for measurement and in particular for the
positioning measurement the delay can be longer e.g. 200 ms to 1
second. In particular when network node performs measurement itself
on at least UE UL signals then it may delay sending the IDC
configuration to the user equipment 10. Sending the IDC
configuration with limited configuration parameter(s) value: In
this case the network node may only allow the user equipment 10 to
have limited configuration e.g. total number of denial subframes
not more than 10. The configuration parameters are adapted to the
operations that are on-going or to be configured by the network
such as measurements. In this way the impact of idle subframes
created by the user equipment 10 on the on-going radio operations
will be reduced or minimized. Therefore performance degradation may
be reduced. Combination of sending the IDC configuration with delay
and limited configuration parameter(s) value: This method can be
used by the network node when for example different radio operation
tasks are performed over longer period of time e.g. scheduling
followed by radio measurements etc.
The network node may also take into account the information related
to radio tasks received from other nodes, e.g. from the positioning
node 13 when the network node is e.g. the radio base station 12,
and/or the user equipment 10 when determining when to adapt the IDC
configuration and what type of adaptation should be applied. For
example information related to positioning, e.g. E-CID, OTDOA etc,
received from positioning node 13 and/or indication from the user
equipment 10 and/or determined by cross layer communication, e.g.
by reading LPP messages sent between the user equipment 10 and
positioning node 13 in LTE.
Action 1402.
The network node may receive the report from the user equipment 10
indicating capability of the user equipment 10. The capability
indicates that the user equipment 10 is capable of performing a
radio measurement which meets one or more requirements related to
the radio measurement provided the IDC configuration meets a
certain condition.
Action 1403.
The network node may determine the IDC configuration according to a
rule, corresponding to the condition checked at the user equipment
10, that will ensure consistent user equipment behaviour and/or
will ensure that the user equipment 10 meets one or more
requirements related to the radio measurement. The determination of
the IDC configuration may be based on the received capability.
Action 1404.
The network node configures the user equipment 10 with an IDC
configuration for at least one IDC scheme, which IDC configuration
enables the user equipment 10 to perform a radio measurement which
meets one or more requirements related to the radio measurement
provided the IDC configuration meets a certain condition. The
certain condition may comprise that the received IDC configuration
comprises a certain range of parameters. Th certain range of
parameters may comprise certain IDC autonomous denial parameters.
The IDC autonomous denial parameters may in its turn comprise that
not more than M IDC autonomous denial subframes are configured over
certain IDC autonomous denial validity period. The certain range of
parameters may alternatively comprise a certain IDC subframe
pattern. The certain range of parameters may e.g. comprise that at
least M number of subframes are available for E-UTRAN operation
over certain time period. The certain range of parameters comprises
a list of one or more subframe patterns indicating which HARQ
process E-UTRAN is required to abstain from using.
Action 1405.
The network node may perform one or more radio operation tasks or
actions based on the received capability and/or the IDC
configuration.
In order to perform the method a network node is provided. FIG. 15
shows a network node according to embodiments herein. The network
node, exemplified herein as the radio base station 12, the
positioning node or a D2D UE is adapted for enabling the user
equipment 10 to perform a radio measurement in the communications
network 1. The user equipment 10 is IDC capable and the network
node is configured to serve the user equipment 10 in the
communications network.
The network node comprises a configuring circuit 1501 adapted to
configure the user equipment 10 with an IDC configuration for at
least one IDC scheme. The IDC configuration enables the user
equipment 10 to perform a radio measurement which meets one or more
requirements related to the radio measurement provided the IDC
configuration meets a certain condition. As previously mentioned,
the certain condition may comprise that the received IDC
configuration comprises a certain range of parameters. The certain
range of parameters may comprise certain IDC autonomous denial
parameters. The IDC autonomous denial parameters may comprise that
not more than M IDC autonomous denial subframes are configured over
certain IDC autonomous denial validity period. The certain range of
parameters may comprise certain IDC subframe pattern. The certain
range of parameters may comprise that at least M number of
subframes are available for E-UTRAN operation over certain time
period. The certain range of parameters may comprise a list of one
or more subframe patterns indicating which HARQ process E-UTRAN is
required to abstain from using.
The network node may further comprise a determining circuit 1502
configured to determine the IDC configuration according to a rule
that will ensure consistent user equipment behaviour and/or will
ensure that the user equipment meets one or more requirements
related to the radio measurement.
The network node further comprises a receiving circuit 1503 that
may be configured to receive a report from the user equipment 10
indicating capability of the user equipment 10. The capability
indicates that the user equipment 10 is capable of performing a
radio measurement which meets one or more requirements related to
the radio measurement provided the IDC configuration meets the
certain condition.
The network node may further comprise a determining circuit 1504
configured to determine the IDC configuration based on the received
capability.
Additionally or alternatively, the network node may comprise a
performing circuit 1505 configured to perform one or more radio
operation tasks or actions based on the received capability.
Furthermore, the network node comprises a transmitting circuit
1506. The transmitter 1305 and receiver 1301 may be implemented as
a transceiver in the user equipment 10.
The embodiments herein for enabling the user equipment 10 to
perform the radio measurement in the communications network 1 may
be implemented through one or more processors, such as a processing
circuit 1507 in the network node depicted in FIG. 15, together with
computer program code for performing the functions and/or method
steps of the embodiments herein. The program code mentioned above
may also be provided as a computer program product, for instance in
the form of a data carrier carrying computer program code for
performing embodiments herein when being loaded into the network
node. One such carrier may be in the form of a CD ROM disc. It is
however feasible with other data carriers such as a memory stick.
The computer program code may furthermore be provided as pure
program code on a server and downloaded to the network node.
The network node further comprises a memory 1508 that may comprise
one or more memory units and may be used to store for example data
such as, conditions, requirements, measurements, capability, an
application to perform the methods herein when being executed on
the network node or similar.
According to some embodiments herein a method in the network node,
such as a radio network node, a positioning node, a SON node, an
MDT node, or a D2D UE is disclosed herein comprising: Determining
or predicting UE autonomous denials; Adapting one or more radio
procedures based on determined UE autonomous denials.
The method may be implemented in any network node serving the user
equipment 10 or communicating with the user equipment 10 or
configuring a user equipment 10. Examples of the network nodes are
base station, Node B, eNode B, relay node, donor node serving a
relay node, mobile relay, BSC, RNC, positioning node, MDT, SON,
OSS, O&M, LMU, any UL measuring node performing positioning
measurement etc.
In case of D2D communication the method can be implemented in UEs,
which are D2D capable i.e. can communicate with other UE(s).
According to a further variant a method is provided in the network
node, for extending the measurement period based on conditions that
indicate a UE denial.
According to a further variant the network node is provided
comprising a processor and memory and being adapted to extending
the measurement period based on conditions that indicate a UE
denial.
According to a further variant the conditions that indicate a UE
denial is a signal quality measure falling under a certain
threshold
According to a further variant the conditions that indicate a UE
denial is based on ACK/NACK feedback in response to dummy downlink
transmission
According to a further variant the conditions that indicate a UE
denial is based on triggering transmission of an uplink known
signal.
According to a further variant a method is provided a method in the
network node is provided to determine the allowed autonomous denial
time based on its own measurement period.
According to a further variant the network node is provided
comprising a processor and memory and being adapted to determine
the allowed autonomous denial time based on its own measurement
period.
According to a further variant a method in the network node is
provided, to adapt scheduling to the perceived denied subframes
from the user equipment 10, such that scheduling strategy depends
on how much of the allowed denial subframes have been consumed by
the user equipment 10.
According to a further variant a radio network node is provided
comprising a processor and memory and being adapted to adapt
scheduling to the perceived denied subframes from the user
equipment 10, such that scheduling strategy depends on how much of
the allowed denial subframes have been consumed by the user
equipment 10.
The network node perceives or configures the user equipment 10 with
an IDC configuration for at least one IDC scheme for the user
equipment 10. The IDC configuration may comprise one or more of the
following: IDC autonomous denial, IDC subframe pattern, and DRX
configuration. In some embodiments the network node may receive,
from the user equipment 10, information related to denial periods
over which the user equipment 10 does not operate on Evolved
Universal Terrestrial Radio Access Network, E-UTRAN or on UTRAN.
The network node may then determine or predict time instance when
user equipment 10 will apply autonomous denial due to IDC. In some
embodiments the network node may implicitly determine autonomous
denial by at least one of: comparing signal quality measure to a
threshold, detecting absence of ACK/NACK feedback sent by the user
equipment 10 for the downlink dummy data sent to the user equipment
10; and detecting absence of an uplink transmission of a known
uplink signal in at least a certain subframe.
The perception of the UE denial can be based on explicit signalling
from the user equipment 10 that certain subframes will be denied,
or implicitly realized by the radio network node. These two
mechanisms are described below:
Explicit Determination of UE Autonomous Denial
In case of UE indication mechanism, the user equipment 10 may
signal information related to a pattern of expected denial periods
valid over certain time e.g. valid over the next 5 seconds to the
network node. If the user equipment 10 is involved in D2D
communication then it may signal this to other UEs involving in D2D
communication. Alternatively the network node receiving the
information related to the pattern from UE1 which applies the
denial due to IDC may signal this information to UE2 where UE1 and
UE2 are in D2D communication mode. Yet another alternative is that
the D2D directly receives the information as well as it receives
from the network node to improve the accuracy of the information or
reliability of the information.
The pattern may indicate one or more of the following parameters
associated with the pattern information: reference time to start
the pattern of denial, e.g. system frame number (SFN), size of each
denial e.g. N subframes, frequency or rate of denial, purpose of
denial, e.g. use of WLAN, GNSS, Bluetooth etc. The user equipment
10 may also signal statistics of one or more denial pattern or
denials used by the user equipment 10 in the past. The user
equipment may signal this information for denial of UL subframes,
DL subframes or both. Based on this received information the
network node can determine or predict the time instances when the
user equipment 10 will apply the autonomous denial due to IDC.
Similarly based on this received information the D2D UE, e.g. UE2,
receiving the information can determine or predict the time
instances when the user equipment 10, e.g. UE1, with which it is in
D2D communication will apply the autonomous denial. Below the
network node is differentiated from the second D2D UE, however, as
stated above the network node may be a D2D UE.
Implicit Determination of UE Autonomous Denial
Some examples of implicit realization at the network node or at the
D2D UE of the autonomous subframe denial by UE, i.e. UE1 in case of
D2D, are as follows. More specifically the implicit determination
is done by a radio network node, which can typically be a serving
radio node or can be done by the D2D UE, i.e. by UE2:
Comparing Some Signal Quality Measure to a Threshold
In case of denying an uplink subframe, if a signal measurement
quantity, e.g. such as SNR, SINR, BER, BLER etc, falls below a
certain threshold, the network node or D2D UE can assume a UL
denial by the user equipment 10 i.e. the user equipment 10 does not
transmit any signal in that subframe. The network node or D2D UE
may especially observe the UL signal quality in subframes in which
the UE is scheduled for UL transmission. If signal quality is below
a threshold then it is expected that the UE has denied that
subframe.
ACK/NACK Feedback Based on Dummy DL
According to this method the network node or D2D UE, i.e. UE2 sends
dummy data in the DL to the user equipment 10, i.e. to UE1 in case
of D2D UE, and if no ACK/NACK is received from the user equipment
10 in certain subframes by the said network node or D2D UE then it
may assume these subframes as subframes denied by UE. One trigger
for transmission of the dummy data transmission in the DL is when
the network node or D2D UE sends the maximum allowed denial
subframes to the user equipment 10 e.g. 30 subframe i.e. 30 ms. The
dummy data may comprise of random data which can be sent to the
user equipment 10 over a data channel e.g. PDSCH in the DL.
Triggering Transmission of an Uplink Known Signal
According to this method the network node or D2D UE may use any
type of known signal or sequence that can be used to verify the
presence of UL transmission. If the network node or D2D UE
determines that no signal is present, i.e. not received at the
network node or D2D UE, then it means that the user equipment 10 is
in UL denial. Examples of known UL signals are CSI reports, e.g.
CQI, RI, PMI etc, SRS, DMRS, ACK/NACK or any UL reference or pilot
signals etc.
For example the network node or D2D UE can configure the user
equipment 10 with a CSI reporting with higher frequency e.g. once
every 2 ms. If the CSI report is not received in certain subframes
then the network node or D2D UE may assume that that UL subframe is
denied by the user equipment 10.
Upon determining the autonomous denial executed by the user
equipment 10 due to IDC e.g. pattern of the autonomous denial or
each individual denial as described above, the radio network or D2D
UE may adapt one or more radio operational tasks to compensate for
the UE autonomously denial subframes. Examples of such tasks
are:
Adapting One or More Parameters Related to Signal Measurement
For example in case of measurement adaptation, the network node
and/or D2D UE may extend the measurement period depending upon the
amount of denials etc. In case of network node the adaptation of
parameter(s) is done for UL measurements. In case of D2D UE the
adaptation of parameter(s) can be done for UL and/or DL
measurements performed on signals transmitted by or to the user
equipment 10 which is doing autonomous denial. For example the
radio node or D2D may measure SINR over 200 ms instead of 100 ms in
case the total denial over 100 ms is 20 ms or more.
Adjusting Scheduling of Data in UL and/or DL
For example in case of scheduling adaptation, the network node or
D2D UE (i.e. UE2) may avoid scheduling those subframes which are
expected to be denied by the user equipment 10 (i.e. UE1 in case of
D2D UE) based on the perceived pattern or statistics of denial. In
yet another example the radio node or D2D UE may use more robust
transport format, e.g. lower order modulation like QPSK and/or
lower code rate like 1/3, for scheduling of data to ensure that the
user equipment 10 is able to receive the data with success as much
as possible during the available subframes, i.e. which are not
denied by the user equipment 10. In this way overall system
performance, e.g. bit rate, throughput, is not degraded due to
autonomous denial.
Adapting Configuration Parameter(s) Related to UE Measurement
For example in this case the network node and/or D2D UE may modify
one or more configuration parameter related to the UE measurements
of the user equipment 10 doing autonomous denial, i.e. measurement
performed by UE1 in case of D2D UE. These parameters are sent to
the user equipment 10 doing measurement to enhanced measurement
performance. In one example the network node or D2D UE may
configure much longer time to trigger (TTT) parameter value e.g.
from 640 ms to 1280 ms. In another example higher layer averaging
parameter value, e.g. L3 filtering co-efficient value, can be
extended e.g. from 0.5 second to 1 second. In yet another example
the measurement BW over which the measurement is done can be
extended e.g. from 25 Resource Blocks (RB) (5 MHz) to 50 RBs (10
MHz). The adaption of measurement configuration parameters, e.g.
extending the value, will improve the measurement accuracy when the
user equipment 10 cannot perform measurement in certain subframes
due to idle periods created by the autonomous denial.
Selecting Another UE for D2D Communication
The network node managing D2D communication and/or the D2D UE
itself, i.e. UE2, may decide to select another UE, e.g. a UE3, for
establishing D2D communication in case the existing UE, i.e. UE1,
causes large number of denials and/or frequent denials. Especially
if the D2D communication involves delay sensitive service or
critical service like positioning or emergency call etc. then the
network node and/or D2D UE may select another UE, not causing
denials or causing fewer denials than UE1, for D2D
communication.
Adapting One or More Parameters Related to Positioning
For example the positioning node 13, e.g. E-SMLC in LTE, adapts the
positioning configuration, e.g. assistance data for positioning,
sent to the user equipment 10 while taking into account the IDC
autonomous denials e.g. carrier frequency on which measurement is
done, selection between different positioning measurements for
positioning, e.g. E-CID RSRP and AoA, selection between different
positioning methods, e.g. E-CID and OTDOA, delaying in sending the
positioning configuration for certain time until the IDC denials
are completed etc. The positioning node 13 may also acquire the
information related to IDC configuration sent the radio network
node to the user equipment 10 in addition to the pattern of the IDC
denials applied by the user equipment 10. The former information be
acquired by the positioning node 13 from the serving radio node
(over LPPa) of the user equipment 10 or from the user equipment 10
itself (over LPP). The positioning node 13 may also forward the
received information related to the IDC configuration and/or the
pattern of the IDC denials to other nodes such as measuring node
performing positioning measurements, e.g. LMU. The measuring node
may use this information to adapt its configuration related to
measurement e.g. only measure on UE signals in those subframes
which are not denied by the user equipment 10.
Adapting Radio Operation Depending Upon Completion Level of
Denial
Another embodiment of the disclosure the network node or D2D UE
determines when the total number of denial subframes is completed
during the validity period. The determination can be done by
explicit and/or implicit mechanism described earlier. For example
the network can configure the user equipment 10 with a validity
period of 1 second and the maximum number of allowed denial
subframes of 30 ms. Depending upon the IDC scenario the user
equipment 10 may complete the total allowed denial over initial 200
ms. Therefore the network node and/or user equipment 10 may adapt
the radio operation after 200 ms. For example a different radio
operational parameters for the same type of procedure before and
after the maximum denial is completed during the validity period.
In other words the radio operational parameters can be different
during initial 200 ms and during the remaining 800 ms.
According to one aspect a method in the IDC capable user equipment
10 served by the network node of performing at least one radio
measurement is provided. The method comprises, Receiving a
configuration for at least one IDC scheme, e.g. autonomous denial,
IDC subframe etc, from the network node to avoid interference
towards in-device external wireless system; Adapting one or more of
the following: measurement time or evaluation time, measurement
sampling rate, creation of the IDC autonomous gaps, without E-UTRAN
operation, with respect to the measurement sampling, wherein the
adaptation is based on one or more configured IDC parameters;
Performing the measurement based on the adaptation; Using the
performed measurement for one or more radio operation tasks, e.g.
reporting results to the network, performing cell change, radio
link monitoring etc.
According to another aspect a method in the network node serving
the IDC capable user equipment 10 is provided. The method
comprises: Configuration the user equipment 10 with at least one
IDC scheme, e.g. autonomous denial, IDC subframe etc, enabling it
to create IDC gaps without E-UTRAN operation avoid interference
towards in-device external wireless system; Adapting one or more
radio operational procedures depending upon the IDC gaps created by
the user equipment 10 according to configured IDC scheme, which
adaptation is one or more of the following: Extending the
measurement period based on condition(s) that indicates the UE
denial. The condition(s) can be a signal quality measurement by
comparing to a threshold or feedback response to dummy data
transmission; Determining the allowed autonomous denial time based
on its own measurement period. Adapting scheduling to the perceived
denied subframes from the user equipment 10, such that e.g. when
user equipment 10 has consumed all of its allowed denial subframes
within the validity time, the network node can schedule the user
equipment 10 more aggressively. Configuring measurement gaps or a
measurement requiring autonomous gaps, e.g. CGI, such that they
don't overlap with the IDC gaps in which there is no E-UTRAN
operation.
According to a further aspect a method in the IDC capable user
equipment 10 served by the network node and capable of performing
at least one radio measurement is provided. The method comprises,
Reporting its capability to the network node whether it is capable
of adapting one or more of measurement time or evaluation time,
measurement sampling rate, creation of the IDC autonomous gaps,
without E-UTRAN operation, with respect to the measurement sampling
and/or meeting one or more pre-defined rule and/or requirements
related to measurement when configured with one or more IDC
parameter.
At least according to some embodiments and aspects the methods and
apparatuses provide that the interference avoidance for IDC will
not impact the measurements at the user equipment 10 and the
network node, or will at least alleviate such problems
At least according to some embodiments and aspects the methods and
apparatuses provide that the E-UTRAN procedures are not interrupted
while the user equipment 10 is configured with any of the schemes
for interference avoidance for IDC, or will at least reduce such
issues.
At least according to some embodiments and aspects the methods and
apparatuses provide that the UE requirements are met when the user
equipment 10 is configured with any of the scheme for interference
avoidance for IDC.
At least some of the methods and devices more specifically allow
the measuring node to optimize the measurement period and
measurement sampling time based on the solution that is used for
IDC interference avoidance.
At least some of the methods enable consistent behavior in terms of
measurements, data scheduling etc when user equipment 10 is
configured with any of the IDC scheme.
At least some of the embodiments provide methods of measurements
when IDC interference avoidance is used.
At least some of the methods and devices also enable adaptation of
the parameters related to the IDC interference avoidance solutions
to protect the radio related measurement operations.
The methods, devices, apparatuses and circuits summarized above can
be used to improve the performance of user equipment and network
nodes, such as Node B, positioning node, D2D UE, eNodeB, RBS etc.
in different radio communication technologies supporting devices
with co-existing radio transmission/reception, for example. Of
course, the present disclosure is not limited to the
above-summarized features and advantages. Indeed, those skilled in
the art will recognize additional features and advantages upon
reading the following detailed description, and upon viewing the
accompanying drawings.
Embodiments herein are described above with reference to the
accompanying drawings, in which examples of embodiments are shown.
Embodiments may, however, be embodied in many different forms and
should not be construed as limited to the embodiments set forth
herein. It should also be noted that these embodiments are not
mutually exclusive. Thus, components or features from one
embodiment may be assumed to be present or used in another
embodiment, where such inclusion is suitable.
The network node, e.g. serving radio node 12, positioning node 13
etc, may also take one or more action based on one or more
pre-defined rules. For instance in preceding exemplary pre-defined
rules the network node may not configure both measurement gaps and
IDC scheme at the same time for the same UE.
In another example the network node may configure both measurement
gaps and IDC scheme at the same time for the same user equipment 10
provided the IDC gaps and certain specific signals, which are
received and/or transmitted by the user equipment 10 don't overlap
or at least only partially overlap.
Embodiments herein are described with reference to the accompanying
drawings, in which examples of embodiments are shown. However,
solutions may be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein. It should
also be noted that these embodiments are not mutually exclusive.
Thus, components or features from one embodiment may be assumed to
be present or used in another embodiment, where such inclusion is
suitable.
For purposes of illustration and explanation only, these and other
embodiments of the present disclosure are described herein in the
context of operating in a RAN that communicates over radio
communication channels with wireless terminals, also referred to as
user equipment, or "UEs". More particularly, specific embodiments
are described in the context of systems using Wideband
Code-Division Multiple Access (W-CDMA) technology and/or High-Speed
Downlink Packet Access (HSDPA) technology, as standardized by the
membership of the 3.sup.rd Generation Partnership Project (3GPP).
It will be understood, however, that the present disclosure is not
limited to such embodiments and may be embodied generally in
various types of communication networks. As used herein, the terms
mobile terminal, wireless terminal, or user equipment can refer to
any device that receives data from a communication network, and may
include, but are not limited to, a mobile telephone ("cellular"
telephone), laptop/portable computer, pocket computer, hand-held
computer, and/or desktop computer.
Also note that the use of terminology such as "base station", which
may be referred to in various contexts as NodeB or radio base
station, for example, and "wireless terminal," "mobile terminal,"
or "wireless device", often referred to as "UE" or "User
Equipment", should be considering non-limiting and does not
necessarily imply a certain hierarchical relation between two
particular nodes of a communication link. In general, a base
station, e.g., a "NodeB", and a wireless terminal, e.g., a "UE",
may be considered as examples of respective different
communications devices that communicate with each other over a
wireless radio channel. While embodiments discussed herein may
focus on wireless transmissions in a downlink from a NodeB to a UE,
the disclosed techniques may also be applied, for example, to
uplink transmissions in some contexts. As a result, several
embodiments described in detail below, including modified versions
of the receiver circuit 1301,1501 pictured in FIGS. 13,15, may be
suitable for use in various wireless terminals, base stations, or
both. It will be appreciated, of course, that the details of
accompanying circuitry, including antennas, antenna interface
circuits, radio-frequency circuits, and other control and base band
circuits, will vary, depending on the specific application of the
techniques disclosed herein. Because these details are not
necessary to a complete understanding of the present embodiments,
those details are generally omitted in the following discussion and
in the accompanying figures.
As will be readily understood by those familiar with communications
receiver design, the several functions disclosed herein may be
implemented using digital logic and/or one or more
microcontrollers, microprocessors, or other digital hardware. In
some embodiments, several or all of the various functions may be
implemented together, such as in a single application-specific
integrated circuit (ASIC), or in two or more separate devices with
appropriate hardware and/or software interfaces between them.
Several of the methods may be implemented on a processor shared
with other functional components of a wireless terminal, for
example.
Alternatively, several of the functional elements of the
transceiver processing circuits discussed above may be provided
through the use of dedicated hardware, while others are provided
with hardware for executing software, in association with the
appropriate software or firmware. Thus, the term "processor" or
"controller" as used herein does not exclusively refer to hardware
capable of executing software and may implicitly include, without
limitation, digital signal processor (DSP) hardware, read-only
memory (ROM) for storing software, random-access memory for storing
software and/or program or application data, and non-volatile
memory. Other hardware, conventional and/or custom, may also be
included. Designers of communications receivers will appreciate the
cost, performance, and maintenance tradeoffs inherent in these
design choices.
It will be appreciated that the foregoing description and the
accompanying drawings represent non-limiting examples of the
methods and apparatus taught herein. As such, the apparatus and
techniques taught herein are not limited by the foregoing
description and accompanying drawings. Instead, the present
disclosure is limited only by the following claims and their legal
equivalents.
ABBREVIATIONS
BS Base Station CID Cell Identity CRS Cell-specific Reference
Signal DL Downlink ID Identity IDC In-Device Coexistence ISM
Industrial, Scientific and Medical L1 Layer 1 L2 Layer 2 LTE Long
Term Evolution MAC Medium Access Control MDT Minimization of drive
test OFDM Orthogonal Frequency Division Multiplexing PBCH Physical
Broadcast Channel PCFICH Physical Control format Indicator PDCCH
Physical Downlink Control Channel PDSCH Physical Downlink Shared
Channel PHICH Physical Hybrid ARQ Indicator Cahnnel PSS Primary
Synchronization Signal RAT Radio Access Technology RE Resource
Element RB Resource Block RRM Radio Resource Management RSRQ
Reference signal received quality RSRP Reference signal received
power SFN Single Frequency Network SRS Sounding Reference Signal
SSS Secondary Synchronization Signal UE User Equipment UL Uplink
RSTD Reference signal time difference SON Self Organizing Network
RSSI Received signal strength indicator O&M Operational and
Maintenance OSS Operational Support Systems OTDOA Observed time
difference of arrival
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